Highly Stable Single-Mode Semiconductor Laser and Control System Based on Dynamic Wavefront Shaping

Abstract

This invention provides a highly stable single-mode semiconductor laser and its control system based on dynamic wavefront shaping, relating to the field of semiconductor laser technology. It includes a semiconductor laser gain module, a dynamic wavefront shaping module, a single-mode screening module, and a laser output module, all optically coupled sequentially. The semiconductor laser gain module is composed of a quantum well structure gain chip. The active region surface of the gain chip integrates a distributed feedback grating and a surface plasmon structure, which are bonded to the active region surface through a surface etching process. This invention achieves real-time adaptive control of the entire laser output process through the dynamic wavefront shaping module and a multi-parameter closed-loop control system. This system can rapidly detect and compensate for wavefront distortion under complex disturbance environments, significantly reducing the response delay and manual intervention required by traditional static correction.

Description

Technical Field

[0001] This invention relates to the field of semiconductor laser technology, specifically to a highly stable single-mode semiconductor laser and its control system based on dynamic wavefront shaping. Background Technology

[0002] With the rapid development of fields such as optical communication, precision manufacturing, and quantum computing, the performance requirements for semiconductor lasers are increasing. Especially in terms of high stability and single-mode output, existing technologies have been widely applied in fiber optic communication systems, lidar, and bio-imaging devices. For example, traditional distributed feedback (DFB) lasers, which achieve single-mode operation through grating structures, have been deployed on a large scale in the telecommunications field, while surface plasmon enhancement technology is used to improve laser gain efficiency and plays a key role in nanophotonic devices. Meanwhile, external cavity feedback and temperature control systems are also being integrated into laser modules to improve environmental adaptability.

[0003] However, existing semiconductor laser technology faces the following key technical challenges in achieving highly stable single-mode output:

[0004] Environmental disturbances cause severe wavefront distortion. Traditional lasers rely on static optical elements to correct the wavefront, but these are sensitive to temperature, vibration, or atmospheric turbulence, resulting in decreased beam quality and unstable modes, making them unable to adapt to dynamic environments in real time.

[0005] The single-mode selection and linewidth control precision are insufficient. Although existing DFB gratings or external cavity structures can suppress multimode, the side-mode suppression ratio is limited, and the linewidth is easily affected by current fluctuations, making it impossible to achieve kHz-level compression, which limits precision applications.

[0006] The system has weak stability and noise suppression capabilities. Traditional control systems adjust temperature and current through simple feedback, but lack multi-parameter closed-loop coordination. Noise (such as relative intensity noise) can easily cause power fluctuations, affecting long-term reliable operation.

[0007] Therefore, a highly stable single-mode semiconductor laser and control system based on dynamic wavefront shaping is needed to solve the above problems. Summary of the Invention

[0008] To achieve the above objectives, the present invention provides the following technical solution: a highly stable single-mode semiconductor laser based on dynamic wavefront shaping, comprising a semiconductor laser gain module, a dynamic wavefront shaping module, a single-mode screening module, and a laser output module, which are optically coupled sequentially, wherein:

[0009] The semiconductor laser gain module is composed of a quantum well structure gain chip. The active region surface of the gain chip is integrated with a distributed feedback grating and a surface plasmon structure. The distributed feedback grating and the surface plasmon structure are combined on the active region surface through a surface etching process. The surface plasmon structure is composed of an array of metal nanoparticles and embedded in the periodic gaps of the distributed feedback grating.

[0010] The dynamic wavefront shaping module consists of an adaptive optics modulator, a wavefront detection unit, and a beam shaping submodule. The beam shaping submodule is composed of an aspherical lens group and is placed at the output end of the semiconductor laser gain module. The aspherical lens group collimates and shapes the diverging beam output from the semiconductor laser gain module into a Gaussian beam before it is incident on the adaptive optics modulator. The wavefront detection unit is composed of an integrated focal plane array sensor and is placed in the output optical path of the adaptive optics modulator. The integrated focal plane array sensor collects the laser wavefront phase and amplitude information after being shaped by the adaptive optics modulator and transmits it to the control system via a data line. The adaptive optics modulator is composed of a liquid crystal spatial light modulator and is placed between the beam shaping submodule and the single-mode screening module. The liquid crystal spatial light modulator adjusts the laser wavefront phase distribution through a pixel array.

[0011] The single-mode screening module is composed of a hybrid structure of an integrated photonic crystal grating and a ring resonant cavity. The integrated photonic crystal grating is embedded in the cavity wall of the ring resonant cavity and coupled to the optical path of the ring resonant cavity through a photonic crystal aperture array.

[0012] The laser output module consists of an adaptive fiber coupler and an optical isolator. The adaptive fiber coupler integrates a microelectromechanical system and is located at the output end of the single-mode screening module. The microelectromechanical system adjusts the coupling position through an actuator. The optical isolator is located at the output end of the adaptive fiber coupler and blocks reflected light through a magneto-optical crystal.

[0013] The control system for a highly stable single-mode semiconductor laser based on dynamic wavefront shaping includes a high-precision closed-loop control module electrically connected to the semiconductor laser gain module and the dynamic wavefront shaping module of the laser. The high-precision closed-loop control module consists of a temperature control unit, a current control unit, and an integrated decision unit. The temperature control unit is connected to the gain chip of the semiconductor laser gain module through a thermal conductivity interface, and the current control unit is connected to the gain chip through a wire. The integrated decision unit is connected to the temperature control unit and the current control unit through a data bus and fuses sensor data, including temperature signals, current signals, and wavefront information. The integrated decision unit is composed of a microprocessor chip and processes the fused data through internal algorithm circuits to generate control commands. The control commands are transmitted to the temperature control unit and the current control unit through the data bus.

[0014] Preferably, the high-precision closed-loop control module is composed of a wavefront feedback control unit. The wavefront feedback control unit is connected to the wavefront detection unit of the dynamic wavefront shaping module through a signal line and to the adaptive optics modulator through a drive interface. The wavefront feedback control unit is composed of a signal processor and receives the phase and amplitude information collected by the wavefront detection unit. The signal processor is composed of an analog-to-digital conversion circuit and a calculation circuit and converts the phase and amplitude information into a compensation signal. The compensation signal is transmitted to the adaptive optics modulator through the drive interface, and the adaptive optics modulator adjusts the pixel array according to the compensation signal.

[0015] Preferably, the high-precision closed-loop control module consists of a power stabilization control unit and a noise suppression unit. The power stabilization control unit is optically coupled to the laser output module via a photodetector and collects output power and spectral line information. The photodetector is composed of a photodiode array and converts the collected information into an electrical signal. The electrical signal is transmitted to the processing circuit of the power stabilization control unit via a feedback line. The processing circuit is composed of an operational amplifier and a filter and generates an adjustment signal. The adjustment signal is transmitted to the current control unit and the wavefront feedback control unit via a control line. The noise suppression unit is composed of a noise compression circuit and integrated into the signal path of the high-precision closed-loop control module. The noise compression circuit is composed of a quantum noise compression component and is connected to the noise source via a photoelectric feedback loop.

[0016] Preferably, the temperature control unit is composed of a combination structure of a thermoelectric cooler and an integrated fiber Bragg grating temperature sensor. The thermoelectric cooler is in contact with the substrate of the gain chip through a Peltier effect element. The integrated fiber Bragg grating temperature sensor is embedded in the heat transfer path of the thermoelectric cooler and connected to a signal processor through an optical fiber. The signal processor is composed of an optical demodulation circuit and converts temperature changes into electrical signals. The electrical signals are transmitted to the driver of the thermoelectric cooler through a closed-loop circuit. The driver is composed of a power amplifier and adjusts the current direction of the thermoelectric cooler.

[0017] Preferably, the current control unit consists of a laser diode driver and an active noise cancellation circuit. The laser diode driver is composed of a constant current source circuit and is connected to the electrodes of the gain chip via wires. The active noise cancellation circuit consists of an adaptive filter and an electromagnetic compatibility shielding structure. The adaptive filter is placed at the output of the constant current source circuit and monitors current fluctuations through a feedback loop. The feedback loop consists of a sampling resistor and a comparator and generates a correction signal. The correction signal is transmitted to the adjustment module of the adaptive filter through internal circuitry. The electromagnetic compatibility shielding structure consists of a metal shell surrounding the entire current control unit and grounded.

[0018] Preferably, the wavefront feedback control unit is composed of an adaptive algorithm circuit, which is composed of a digital signal processor and integrated on the main board of the wavefront feedback control unit. The digital signal processor receives phase and amplitude information through an input interface and performs algorithm calculations. The algorithm calculations include filtering and compensation calculations. The compensation calculation results are transmitted to an adaptive optical modulator through an output interface. The adaptive optical modulator adjusts the voltage distribution of the liquid crystal pixels according to the compensation calculation results. The voltage distribution is phase-adjusted through a driving array.

[0019] Preferably, the power stabilization control unit integrates a spectral line monitoring function, which is composed of a spectral analysis circuit and connected to a photodetector. The spectral analysis circuit is composed of a spectrometer and a detection array and analyzes the spectral line information. The spectral line information is transmitted to the central processing unit of the power stabilization control unit via a data line. The central processing unit is composed of a microcontroller and generates an optimization signal. The optimization signal is transmitted to the resonant cavity adjuster of the single-mode screening module via a control bus. The resonant cavity adjuster is composed of a piezoelectric element and changes the cavity length of the ring resonant cavity.

[0020] Preferably, the high-precision closed-loop control module is composed of a central processing unit, which is composed of a multi-core processor integrated with a graphics processing unit accelerator and acquires temperature, current, wavefront phase, output power and environmental disturbance data through a bus interface. The bus interface includes an analog-to-digital converter and a multiplexer. The multi-core processor processes the acquired data through parallel computing and generates coordination instructions. The coordination instructions are transmitted to the temperature control unit, current control unit, wavefront feedback control unit and power stabilization control unit through the output port. The graphics processing unit accelerator is composed of a graphics processing chip and processes the image calculation of the wavefront phase data.

[0021] Preferably, the control system includes the following steps:

[0022] Sp1 connects to the gain chip of the semiconductor laser gain module through the temperature control unit, collects temperature signals and adjusts the current direction of the thermoelectric cooler to regulate the temperature of the gain chip;

[0023] Sp2 connects to the gain chip via the current control unit, acquires the current signal, and generates a correction signal through the active noise cancellation circuit to adjust the drive current.

[0024] Sp3: The laser wavefront phase and amplitude information after being shaped by the adaptive optic modulator is acquired by the wavefront detection unit and transmitted to the wavefront feedback control unit through the signal line.

[0025] Sp4, the wavefront feedback control unit receives phase and amplitude information, converts it into a compensation signal through a signal processor, and transmits it to the adaptive optics modulator through the drive interface to adjust the pixel array;

[0026] Sp5: The photodetector of the power stabilization control unit collects the output power and spectral information of the laser output module, and generates an adjustment signal that is transmitted to the current control unit and the wavefront feedback control unit.

[0027] The SP6 central processing unit collects temperature, current, wavefront phase, output power, and environmental disturbance data through a bus interface. It processes the data through a multi-core processor and generates coordination instructions, which are then transmitted to the temperature control unit, current control unit, wavefront feedback control unit, and power stabilization control unit to achieve closed-loop feedback adjustment of the laser output wavefront and stability.

[0028] This invention provides a highly stable single-mode semiconductor laser and its control system based on dynamic wavefront shaping. It offers the following advantages:

[0029] 1. This invention achieves real-time adaptive control throughout the laser output process via a dynamic wavefront shaping module and a multi-parameter closed-loop control system. This system can rapidly detect and compensate for wavefront distortion under complex disturbance environments, significantly reducing the response delay and manual intervention required by traditional static correction. By integrating an adaptive optics modulator and a precision feedback mechanism, it not only improves the stabilization speed of beam quality but also ensures mode purity and power consistency, greatly enhancing the overall operating efficiency of the laser. This better meets the high-precision application requirements in dynamic environments and is particularly suitable for scenarios such as optical communication, precision machining, and quantum optics.

[0030] 2. This invention achieves precise selection and enhancement of laser modes by combining a distributed feedback grating with a surface plasmon structure in the semiconductor laser gain module, and a hybrid design of an integrated photonic crystal grating with a ring resonator in the single-mode selection module. Through the synergistic utilization of the localization of the optical field in the gain region and the photonic bandgap effect, the system effectively suppresses side-mode competition and improves single-mode purity, enhancing the accuracy of single-mode selection and linewidth control. This ensures the coherence and spectral stability of the output laser, thereby reducing application errors caused by mode instability.

[0031] 3. This invention achieves comprehensive real-time optimization of system parameters through multi-unit collaboration of a high-precision closed-loop control module, including temperature control, current stabilization, wavefront feedback, power adjustment, and noise suppression. This adaptive capability, integrating multi-sensor data fusion and coordinated command mechanisms, enables the laser to maintain parameter stability during long-term operation, reduces power drift caused by noise and fluctuations, improves the system's anti-interference capability and long-term reliability, and ensures the repeatability of experimental or application results. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the laser configuration of the present invention;

[0033] Figure 2 This is a core framework diagram of the control system of the present invention;

[0034] Figure 3 This is a flowchart of the control system operation of the present invention. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Specific Implementation Example 1:

[0037] like Figures 1 to 3 As shown, a highly stable single-mode semiconductor laser based on dynamic wavefront shaping includes a semiconductor laser gain module, a dynamic wavefront shaping module, a single-mode screening module, and a laser output module, which are optically coupled sequentially.

[0038] The semiconductor laser gain module is composed of a quantum well structure gain chip. The active region surface of the gain chip is integrated with a distributed feedback grating and a surface plasmon structure. The distributed feedback grating and the surface plasmon structure are combined on the active region surface through a surface etching process. The surface plasmon structure is composed of an array of metal nanoparticles and embedded in the periodic gaps of the distributed feedback grating.

[0039] The dynamic wavefront shaping module consists of an adaptive optics modulator, a wavefront detection unit, and a beam shaping submodule. The beam shaping submodule is composed of an aspherical lens group and is placed at the output end of the semiconductor laser gain module. The aspherical lens group collimates and shapes the diverging beam output from the semiconductor laser gain module into a Gaussian beam before it is incident on the adaptive optics modulator. The wavefront detection unit is composed of an integrated focal plane array sensor and is placed in the output optical path of the adaptive optics modulator. The integrated focal plane array sensor collects the laser wavefront phase and amplitude information after being shaped by the adaptive optics modulator and transmits it to the control system via a data line. The adaptive optics modulator is composed of a liquid crystal spatial light modulator and is placed between the beam shaping submodule and the single-mode screening module. The liquid crystal spatial light modulator adjusts the laser wavefront phase distribution through a pixel array.

[0040] The single-mode screening module consists of a hybrid structure of an integrated photonic crystal grating and a ring resonant cavity. The integrated photonic crystal grating is embedded in the cavity wall of the ring resonant cavity and coupled to the optical path of the ring resonant cavity through a photonic crystal aperture array.

[0041] The laser output module consists of an adaptive fiber coupler and an optical isolator. The adaptive fiber coupler integrates a microelectromechanical system and is located at the output end of the single-mode screening module. The microelectromechanical system adjusts the coupling position through an actuator. The optical isolator is located at the output end of the adaptive fiber coupler and blocks reflected light through a magneto-optical crystal.

[0042] The control system includes a high-precision closed-loop control module electrically connected to the semiconductor laser gain module and dynamic wavefront shaping module of the laser. The high-precision closed-loop control module consists of a temperature control unit, a current control unit, and an integrated decision unit. The temperature control unit is connected to the gain chip of the semiconductor laser gain module through a thermal conduction interface, and the current control unit is connected to the gain chip through a wire. The integrated decision unit is connected to the temperature control unit and the current control unit through a data bus and fuses sensor data, including temperature signals, current signals, and wavefront information. The integrated decision unit is composed of a microprocessor chip and processes the fused data through an internal algorithm circuit to generate control commands. The control commands are transmitted to the temperature control unit and the current control unit through the data bus.

[0043] The high-precision closed-loop control module consists of a wavefront feedback control unit. The wavefront feedback control unit is connected to the wavefront detection unit of the dynamic wavefront shaping module via a signal line and to the adaptive optics modulator via a drive interface. The wavefront feedback control unit is composed of a signal processor and receives the phase and amplitude information collected by the wavefront detection unit. The signal processor is composed of an analog-to-digital conversion circuit and an arithmetic circuit and converts the phase and amplitude information into a compensation signal. The compensation signal is transmitted to the adaptive optics modulator via the drive interface. The adaptive optics modulator adjusts the pixel array according to the compensation signal.

[0044] The high-precision closed-loop control module consists of a power stabilization control unit and a noise suppression unit. The power stabilization control unit is optically coupled to the laser output module through a photodetector and collects output power and spectral line information. The photodetector is composed of a photodiode array and converts the collected information into an electrical signal. The electrical signal is transmitted to the processing circuit of the power stabilization control unit through a feedback line. The processing circuit is composed of an operational amplifier and a filter and generates an adjustment signal. The adjustment signal is transmitted to the current control unit and the wavefront feedback control unit through a control line. The noise suppression unit is composed of a noise compression circuit and integrated into the signal path of the high-precision closed-loop control module. The noise compression circuit is composed of a quantum noise compression component and is connected to the noise source through a photoelectric feedback loop.

[0045] The temperature control unit consists of a combination of a thermoelectric cooler and an integrated fiber Bragg grating temperature sensor. The thermoelectric cooler contacts the substrate of the gain chip through a Peltier effect element. The integrated fiber Bragg grating temperature sensor is embedded in the heat transfer path of the thermoelectric cooler and connected to the signal processor through an optical fiber. The signal processor consists of an optical demodulation circuit and converts temperature changes into electrical signals. The electrical signals are transmitted to the driver of the thermoelectric cooler through a closed-loop circuit. The driver consists of a power amplifier and adjusts the current direction of the thermoelectric cooler.

[0046] The current control unit consists of a laser diode driver and an active noise cancellation circuit. The laser diode driver is composed of a constant current source circuit and is connected to the electrodes of the gain chip via wires. The active noise cancellation circuit consists of an adaptive filter and an electromagnetic compatibility shielding structure. The adaptive filter is placed at the output of the constant current source circuit and monitors current fluctuations through a feedback loop. The feedback loop consists of a sampling resistor and a comparator and generates a correction signal. The correction signal is transmitted to the adjustment module of the adaptive filter through internal circuitry. The electromagnetic compatibility shielding structure consists of a metal shell surrounding the entire current control unit and is grounded.

[0047] The wavefront feedback control unit is composed of an adaptive algorithm circuit, which is composed of a digital signal processor and integrated on the main board of the wavefront feedback control unit. The digital signal processor receives phase and amplitude information through the input interface and performs algorithm calculations. The algorithm calculations include filtering and compensation calculations. The compensation calculation results are transmitted to the adaptive optical modulator through the output interface. The adaptive optical modulator adjusts the voltage distribution of the liquid crystal pixels according to the compensation calculation results. The voltage distribution is phase-adjusted through the driving array.

[0048] The power stabilization control unit integrates spectral line monitoring functionality. This functionality consists of a spectral analysis circuit connected to a photodetector. The spectral analysis circuit comprises a spectrometer and a detection array, which analyzes spectral line information. This spectral line information is transmitted via a data line to the central processing unit (CPU) of the power stabilization control unit. The CPU, composed of a microcontroller, generates an optimization signal. This optimization signal is transmitted via a control bus to the resonant cavity adjuster of the single-mode screening module. The resonant cavity adjuster, composed of piezoelectric elements, changes the cavity length of the ring resonant cavity.

[0049] The high-precision closed-loop control module consists of a central processing unit, which is composed of a multi-core processor, an integrated graphics processing unit, and an accelerator. It acquires temperature, current, wavefront phase, output power, and environmental disturbance data through a bus interface. The bus interface includes an analog-to-digital converter and a multiplexer. The multi-core processor processes the acquired data through parallel computing and generates coordination instructions. The coordination instructions are transmitted to the temperature control unit, current control unit, wavefront feedback control unit, and power stabilization control unit through the output port. The graphics processing unit accelerator is composed of a graphics processor chip and performs image processing on the wavefront phase data. Specific Implementation Example 2:

[0051] like Figures 1 to 3 As shown below, the semiconductor laser body is described in detail. This laser includes a semiconductor laser gain module, a dynamic wavefront shaping module, a single-mode selection module, and a laser output module, all optically coupled sequentially. The semiconductor laser gain module is the core light-emitting part of the laser, responsible for generating the initial laser gain beam through electrical pumping. The dynamic wavefront shaping module is an optical correction device used to detect and adjust laser wavefront distortion in real time to improve beam quality. The single-mode selection module is a mode selection component used to select a single longitudinal mode from multimode lasers, ensuring mode purity and narrow linewidth of the output laser. The laser output module is an output optimization device used to efficiently couple the laser to an external system and isolate reflection interference. Each module is optically connected through a precision optical alignment system (such as a high-precision optical platform and collimating lens group), ensuring that the beam, after being generated by the semiconductor laser gain module, sequentially passes through the dynamic wavefront shaping module, the single-mode selection module, and the laser output module. The specific connection method is as follows: the output end of the semiconductor laser gain module and the input end of the dynamic wavefront shaping module are tightly connected through an anti-reflection coating interface to reduce light reflection loss; the output end of the dynamic wavefront shaping module and the input end of the single-mode screening module are connected through a short-distance waveguide structure to achieve stable beam transmission; the output end of the single-mode screening module and the input end of the laser output module are connected through micro-optical fixing components to form a complete optical path. In terms of data flow, optical data (laser beam) is output from the semiconductor laser gain module as input, enters the dynamic wavefront shaping module for phase adjustment, and then outputs a shaped beam as input to the single-mode screening module; the single-mode screening module outputs a filtered single-mode beam as input to the laser output module, ultimately outputting a stable laser signal. Simultaneously, the electrical data flow includes phase and amplitude information collected by the wavefront detection unit as input, transmitted through a data line to the control system for processing, outputting a compensation signal, and returning to the adaptive optics modulator to adjust the beam; the entire data transmission path uses low-noise cables and digital interfaces to ensure signal integrity, with the input being the original wavefront data and the output being the corrected beam parameters.

[0052] The semiconductor laser gain module consists of a quantum well structure gain chip. This quantum well structure gain chip is the core light-emitting component of a semiconductor laser diode. Its function is to improve carrier recombination efficiency through quantum confinement, providing high-efficiency laser gain. It is formed on a substrate using molecular beam epitaxy or metal-organic chemical vapor deposition (MOCVD) processes, creating a multilayer semiconductor material structure. The specific hardware components include: a substrate layer (such as gallium arsenide or indium phosphide, providing mechanical support and electrical connections), a lower cladding layer (a high-bandgap material such as aluminum gallium arsenide, used to confine carrier diffusion and improve injection efficiency), an active region (multilayer thin low-bandgap materials such as indium gallium arsenide alternating with high-bandgap barrier layers to form a quantum well, providing optical gain and enhancing radiative recombination by confining electrons and holes in a two-dimensional plane), and an upper cladding layer (similar to the lower cladding layer, used for symmetrical structures to ensure uniform light field distribution). These layers are stacked through epitaxial growth, resulting in a strip-shaped chip approximately several hundred micrometers wide and a few millimeters long. Hardware Description: During operation, current is injected through the positive and negative electrodes (input current signal), which excites electron-hole recombination in the active region to generate photons (output laser gain beam). The data stream is converted from electrical signal input to optical output.

[0053] The active region of the gain chip integrates a distributed feedback grating and a surface plasmon structure. This integration is achieved through electron beam lithography and reactive ion etching: first, a passivation layer is deposited on the active region surface, then a pattern is defined, trenches are etched, and finally, metal is vapor-deposited for filling. The specific hardware components include: the distributed feedback grating, composed of periodic high and low refractive index regions (such as semiconductor trenches filled with air or low refractive index media, with a period approximately half the laser wavelength; its function is to provide built-in optical feedback through Bragg reflection, selecting a specific wavelength and suppressing multimode); and the surface plasmon structure, composed of an array of metal nanoparticles (such as gold or silver particles, 10-50 nanometers in diameter; its function is to enhance the localization of the optical field and improve gain efficiency through surface plasmon polarons), embedded in the grating period gaps to form a metal-dielectric interface. Hardware Description: The distributed feedback grating provides optical feedback (input beam, output specific wavelength selection) through Bragg reflection. The surface plasmon structure supports surface plasmon polarimetric sub-modes, localizing the optical field (input optical field, output enhanced gain). The data stream is the single-mode pre-selected beam output after the incident beam passes through the structure for reflection and localization, and the path is transmitted through the surface interface.

[0054] The dynamic wavefront shaping module consists of an adaptive optics modulator, a wavefront detection unit, and a beam shaping submodule. This module is integrated within an aluminum alloy package and mounted on the optical path via threaded fixing and an adjustment bracket. Its function is to correct laser wavefront distortion in real time, improving beam quality and stability. Specific hardware components include: the beam shaping submodule, composed of an aspherical lens group (multiple optical glass or calcium fluoride lenses, 5-10 mm in diameter, used to correct spherical aberration and astigmatism, converting divergent beams into parallel Gaussian beams); the wavefront detection unit, composed of an integrated focal plane array sensor (complementary metal-oxide-semiconductor or charge-coupled device array, pixel size 5-10 micrometers, resolution 1024x1024, used to measure wavefront gradients or interference fringes and quantify distortion through array pixels); and the adaptive optics modulator, composed of a liquid crystal spatial light modulator (liquid crystal layer sandwiching transparent electrodes, pixel array resolution 1920x1080, pixel pitch 8 micrometers, used to control the phase of liquid crystal molecules through voltage to achieve dynamic wavefront adjustment). Hardware Description: The beam shaping submodule collimates and shapes the diverging beam (input diverging beam, output Gaussian beam, path refracted by lens group); the wavefront detection unit acquires wavefront information (input shaped beam, output phase and amplitude digital signals, path extracted by beam splitter and converted by sensor); the adaptive optics modulator adjusts the phase (input compensation signal, output corrected beam, path driven by voltage to liquid crystal molecules).

[0055] The single-mode selection module consists of a hybrid structure of an integrated photonic crystal grating and a ring resonator. This hybrid structure is fabricated on a silicon-based or III-V semiconductor platform using electron beam lithography and dry etching processes. Its function is to finely select single longitudinal modes and suppress side-mode competition through photonic bandgap and resonator effects. Specific hardware components include: the integrated photonic crystal grating, constructed from a two-dimensional array of air holes (aperture 100-200 nm, period 300-500 nm, its function is to form a photonic bandgap through periodic structure, prohibiting the propagation of certain modes) in a dielectric slab; and the ring resonator, constructed from a ring waveguide (diameter 10-50 μm, width 1-2 μm, its function is to support optical circulation through total internal reflection and select resonant modes). Hardware description: The photonic crystal grating is embedded in the cavity wall and connected to the ring resonator path through lateral coupling, utilizing the photonic bandgap effect to select modes (input shaping beam, output single longitudinal mode beam, data flow path is total internal reflection and bandgap filtering within the waveguide).

[0056] The laser output module consists of an adaptive fiber coupler and an optical isolator. The entire module is encapsulated in a metal housing. Its function is to efficiently couple the filtered laser light to the fiber output and prevent reflected light from interfering with system stability. Specific hardware components include: the adaptive fiber coupler, composed of a microelectromechanical system (MEMS) (a silicon-based micromirror or lens array, 1 mm in size, whose function is to optimize coupling efficiency through micro-adjustment); and the optical isolator, composed of a magneto-optical crystal (such as yttrium iron garnet, 1-2 mm thick, whose function is to rotate polarization through the Faraday effect and block reflected light) placed within a permanent magnet. Hardware description: The MEMS adjusts the position of the coupled beam via an actuator (inputting the filtered beam, outputting the fiber signal, the path is focused and incident); the optical isolator blocks reflections (inputting the coupled light, outputting the isolated beam, the path is rotated polarization through the Faraday effect).

[0057] Through the aforementioned structure and data flow, this laser achieves highly stable single-mode output. Specific Implementation Example 3:

[0059] like Figures 1 to 3 As shown, the following is a detailed description of the control system. This control system includes a high-precision closed-loop control module electrically connected to the semiconductor laser gain module and dynamic wavefront shaping module of the laser. This module is integrated via a multi-layer printed circuit board and employs a negative feedback principle to ensure laser parameter stability. Specific electrical connections include: the temperature control unit is connected to the gain chip via a thermal conductivity interface; the current control unit is connected to the chip electrodes via low-noise wires; and the wavefront feedback control unit is connected to the dynamic wavefront shaping module via signal lines.

[0060] The high-precision closed-loop control module consists of a temperature control unit, a current control unit, and an integrated decision unit. Specific hardware components include: the temperature control unit, which comprises a thermoelectric cooler and a temperature sensor; the current control unit, which comprises a laser diode driver and a noise cancellation circuit; and the integrated decision unit, which comprises a microprocessor chip.

[0061] The high-precision closed-loop control module consists of a wavefront feedback control unit. Specific hardware components include a signal processor comprised of analog-to-digital conversion circuits and arithmetic circuits.

[0062] The high-precision closed-loop control module consists of a power stabilization control unit and a noise suppression unit. Specifically, the hardware components include: the power stabilization control unit, which comprises a photodetector and processing circuitry; and the noise suppression unit, which consists of a noise compression circuit.

[0063] The temperature control unit consists of a combination of a thermoelectric cooler and an integrated fiber Bragg grating temperature sensor. Specific hardware components include: the thermoelectric cooler is composed of Peltier effect elements; the sensor is composed of a fiber Bragg grating; the signal processor is composed of an optical demodulation circuit; and the driver is composed of a power amplifier.

[0064] The current control unit consists of a laser diode driver and an active noise cancellation circuit. Specific hardware components include: the driver is a constant current source circuit; the cancellation circuit consists of an adaptive filter and an electromagnetic compatibility shielding structure; and the feedback loop consists of a sampling resistor and a comparator.

[0065] The wavefront feedback control unit is composed of adaptive algorithm circuitry. Specific hardware components include a digital signal processor integrated on the motherboard, connected via input / output interfaces.

[0066] The power stabilization control unit integrates spectral line monitoring functionality. Specific hardware components include: the spectral line monitoring function, comprised of a spectral analysis circuit including a spectrometer and a detection array; a central processing unit consisting of a microcontroller; and a resonant cavity tuner composed of piezoelectric elements.

[0067] The high-precision closed-loop control module consists of a central processing unit. Specific hardware components include: a multi-core processor integrated with a graphics processing unit accelerator; bus interfaces including analog-to-digital converters and multiplexers; and the graphics processing unit accelerator is composed of a graphics processing chip.

[0068] Complete system control flow:

[0069] The complete control flow of this control system adopts a closed-loop negative feedback mechanism to ensure the coordinated operation of all units, forming a continuous real-time loop from multi-sensor data acquisition to global decision-making and execution adjustments. The specific flow is as follows, ensuring the synchronous stability of temperature, current, wavefront, power, and noise parameters:

[0070] Data acquisition phase: The integrated fiber Bragg grating temperature sensor in the temperature control unit acquires the temperature signal from the gain chip via optical fiber, which is then converted into an electrical signal by the signal processor; the sampling resistor in the current control unit monitors the injected current fluctuations and acquires the current signal through a feedback loop; the wavefront detection unit in the wavefront feedback control unit acquires phase and amplitude information, which is then digitized by the signal processor; the photodetector in the power stabilization control unit acquires output power and spectral line information, which is then converted into an electrical signal by the processing circuit; and the noise suppression unit acquires noise data through a photoelectric feedback loop. All these signals are transmitted uniformly to the bus interface of the central processing unit via a data bus, ensuring synchronous input of multi-source data.

[0071] Data processing and decision-making stages: The multi-core processor of the central processing unit receives the acquired data and performs fusion analysis through parallel computing. The microprocessor chip of the integrated decision unit uses internal algorithm circuits to process the fused temperature, current, and wavefront information, calculating errors and control parameters; the adaptive algorithm circuit of the wavefront feedback control unit performs filtering and compensation calculations to generate compensation signals; the spectral line monitoring function of the power stabilization control unit analyzes spectral line information through spectral analysis circuits, and the central processing unit generates optimized signals; the noise compression circuit of the noise suppression unit processes noise data and performs compression calculations. The accelerator of the graphics processing unit assists in image processing of the wavefront phase data to ensure efficient processing.

[0072] Parameter adjustment stage: Based on the decision results, the temperature control unit transmits the error signal to the power amplifier driver through a closed-loop circuit to adjust the current direction of the thermoelectric cooler and regulate the chip temperature; the adaptive filter of the current control unit generates a correction signal and adjusts the drive current of the constant current source circuit through internal circuitry; the compensation signal of the wavefront feedback control unit is transmitted to the adaptive optics modulator through the drive interface to adjust the pixel array to correct wavefront distortion; the adjustment and optimization signals of the power stabilization control unit are transmitted to the piezoelectric elements of the current control unit, the wavefront feedback control unit, and the resonant cavity adjuster through control lines and control buses to change the cavity length, stable power, and spectral lines of the ring resonant cavity; the noise suppression unit is connected to the noise source through a photoelectric feedback loop to achieve dynamic adjustment.

[0073] Global Coordination and Feedback Phase: The central processing unit monitors all adjustment results. If parameter deviations exceed thresholds (such as temperature fluctuations or wavefront distortion), it generates coordination commands and transmits them through the output port to the temperature control unit, current control unit, wavefront feedback control unit, and power stabilization control unit to achieve priority adjustments (such as stabilizing the temperature first and then compensating for the wavefront). The entire process is executed cyclically, forming negative feedback to ensure the overall coordinated operation of the system and the stability of laser output.

[0074] Through the aforementioned control system, the laser achieves precise stabilization of multiple parameters. Specific Implementation Example 4:

[0076] like Figures 1 to 3 As shown, the operation steps of the control system are coordinated by the software program with the hardware, and each step is executed in a loop to ensure real-time control.

[0077] Sp1 connects to the gain chip of the semiconductor laser gain module via a temperature control unit, acquires temperature signals, and adjusts the current direction of the thermoelectric cooler to regulate the gain chip temperature. Specifically: an integrated fiber Bragg grating temperature sensor acquires changes in the chip substrate temperature via optical fiber, converting the wavelength shift into an electrical signal; a signal processor uses an optical demodulation circuit to process the signal and calculate the error between the set temperature and the actual temperature; this error is transmitted through a closed-loop circuit to the power amplifier driver, which adjusts the current direction of the Peltier effect element in the thermoelectric cooler to achieve temperature stabilization.

[0078] Sp2 connects to the gain chip via the current control unit, acquires the current signal, and generates a correction signal through the active noise cancellation circuit to adjust the drive current. Specifically: a sampling resistor monitors the injected current and generates a feedback voltage signal; a comparator compares the feedback voltage with the set current and calculates the deviation; an adaptive filter uses the least mean square algorithm to process the deviation and generate a correction signal; the correction signal is superimposed onto the constant current source circuit through internal circuitry to adjust the output current and ensure low-noise drive.

[0079] Sp3: The wavefront detection unit acquires the phase and amplitude information of the laser wavefront after it has been shaped by the adaptive optics modulator, and transmits it to the wavefront feedback control unit via a signal line. Specifically: The integrated focal plane array sensor uses a microlens array to segment the wavefront, measures the focal shift, and calculates the phase gradient and amplitude distribution; the data is digitized through an analog-to-digital converter and transmitted to the input interface of the wavefront feedback control unit.

[0080] The Sp4 wavefront feedback control unit receives phase and amplitude information, converts it into a compensation signal via a signal processor, and transmits it to the adaptive optics modulator through a drive interface to adjust the pixel array. Specifically, the signal processor, a field-programmable gate array (FPGA), first uses a finite impulse response (FIR) filter to remove high-frequency noise after receiving data, then calculates the compensation coefficients using a gradient descent optimization algorithm to generate a voltage matrix signal. This signal is transmitted to the liquid crystal spatial light modulator via a digital-to-analog converter interface, where the voltage is adjusted pixel-by-pixel to achieve phase correction.

[0081] Sp5: The photodetector of the power stabilization control unit collects the output power and spectral line information of the laser output module and generates an adjustment signal, which is transmitted to the current control unit and the wavefront feedback control unit. Specifically: The photodiode array detector extracts the optical signal and converts it into an electrical current signal; the processing circuit amplifies the signal using an operational amplifier and filters it with a low-pass filter, calculates the power value and spectral linewidth, compares them with the set values ​​to generate an error adjustment signal; the adjustment signal is transmitted through control lines to the current control unit for adjustment drive and the wavefront feedback control unit for optimization compensation.

[0082] The SP6 central processing unit acquires temperature, current, wavefront phase, output power, and environmental disturbance data via a bus interface. A multi-core processor processes this data and generates coordination instructions, which are then transmitted to the temperature control unit, current control unit, wavefront feedback control unit, and power stabilization control unit. This achieves closed-loop feedback adjustment of the laser output wavefront and stability. Specifically: the bus interface uses an analog-to-digital converter and multiplexer to acquire multiple data streams; the multi-core processor is an advanced RISC Cortex-A series chip, allocating tasks through parallel threads and using a Kalman filter algorithm to fuse data and predict the state; a graphics processing unit (GPU) chip accelerates the fast Fourier transform analysis of the wavefront phase data; and priority coordination instructions are generated and transmitted to each unit via general-purpose input / output ports, forming a global closed loop.

[0083] Through the above steps, this method achieves dynamic high-stability operation of the laser. Specific Implementation Example 5:

[0085] like Figures 1 to 3 As shown, this embodiment provides a detailed description of the core algorithm of the system:

[0086] Adaptive algorithm circuit (for wavefront feedback control unit): The input is phase and amplitude information (digital signals acquired from the wavefront detection unit); the calculation process is that after receiving the information, the circuit iteratively optimizes by adaptively adjusting parameters (such as weighting coefficients) to gradually reduce wavefront distortion error and achieve dynamic compensation; the output is the compensation calculation result, which is transmitted to the adaptive optical modulator to adjust the voltage distribution of the liquid crystal pixels.

[0087] Filtering algorithm operation (for the algorithm operation part of the wavefront feedback control unit): The input is the original phase and amplitude information sequence (received from the input interface); the calculation process is to apply digital filtering operation to the sequence to remove noise interference and retain useful signal components; the output is the filtered data, which is used for subsequent compensation calculation.

[0088] Compensation calculation algorithm operation (for the algorithm operation part of the wavefront feedback control unit): The input is the filtered phase and amplitude information; the calculation process is to calculate the compensation value based on the distortion model, and to achieve wavefront flattening by iteratively solving the phase adjustment parameters; the output is the compensation signal, which is transmitted to the output interface.

[0089] The internal algorithm circuit processes the fused data (for the integrated decision unit): the input is fused sensor data, including temperature signal, current signal and wavefront information (acquired from the data bus); the calculation process is that the circuit fuses the multi-source data, calculates the comprehensive control parameters, and generates instructions; the output is the control instructions, which are transmitted to the temperature control unit and the current control unit. Specific Implementation Example Six:

[0091] like Figures 1 to 3 As shown, the following are specific application examples based on the above content:

[0092] Application Scenario 1: Precision spectral analysis (such as high-resolution spectrometers for gas detection)

[0093] In precision spectral analysis, this laser serves as a narrow-linewidth seed source for detecting trace gases (such as carbon dioxide or methane) in the atmosphere. The system compensates for environmental disturbances through dynamic wavefront shaping, ensuring that the laser linewidth remains stable below the megahertz level, thus achieving high-precision absorption spectrum measurements.

[0094] Step 1: System Preparation. The laser is mounted on the spectrometer platform. The quantum well structure gain chip of the semiconductor laser gain module is connected to the current control unit via electrodes. The adaptive optics modulator of the dynamic wavefront shaping module is aligned with the optical path. The integrated focal plane array sensor of the wavefront detection unit is placed on the output optical path. The ring resonator of the single-mode screening module is connected to the fiber optic probe via the adaptive fiber optic coupler of the laser output module. The central processing unit of the high-precision closed-loop control module is connected to all sensors and actuators via a bus interface to ensure data fusion.

[0095] Step 2: Parameter Setting. Set the laser operating wavelength (e.g., 1550nm, for near-infrared gas absorption), and input the initial temperature (25°C) and current (100mA) target values ​​through the integrated decision unit; initialize the compensation parameters in the adaptive algorithm circuit of the wavefront feedback control unit, set the output power threshold (5mW) in the power stabilization control unit, and activate the photoelectric feedback loop in the noise suppression unit; start the control system, the thermoelectric cooler of the temperature control unit adjusts the chip substrate temperature through the Peltier effect element, and the constant current source circuit of the current control unit provides stable drive.

[0096] Step 3: Real-time Operation. After the laser is started, the semiconductor laser gain module generates an initial diverging beam, which is collimated into a Gaussian beam by the aspherical lens group of the beam shaping submodule. The wavefront detection unit collects phase and amplitude information and transmits it to the digital signal processor of the wavefront feedback control unit to perform filtering and compensation calculations, generating compensation signals to adjust the pixel array of the liquid crystal spatial light modulator and correct distortion caused by thermal disturbance. The single-mode screening module uses a hybrid structure of integrated photonic crystal grating and ring resonator to screen single longitudinal modes. At the same time, the temperature control unit monitors the signal of the integrated fiber Bragg grating temperature sensor, converts it into an electrical signal through the signal processor, and adjusts the direction of the driver current in a closed loop. The adaptive filter of the current control unit generates a correction signal through the feedback loop (sampling resistor and comparator) to eliminate noise. The photodetector of the power stabilization control unit collects the output power and spectral lines, and the processing circuit generates adjustment signals to feed back to the current and wavefront units. The central processing unit collects all data, generates coordination instructions through parallel calculation by a multi-core processor, and transmits them to each unit to achieve closed-loop stabilization.

[0097] Step 4: Output Application. The adaptive fiber coupler of the laser output module adjusts its position via a microelectromechanical system (MEMS) to couple a stable single-mode laser into the fiber optic probe and inject it into the gas sample chamber; the spectrometer detects the absorption spectral lines, and the system compensates for atmospheric turbulence in real time to ensure a measurement accuracy better than 0.01 nm, which is used for generating environmental monitoring reports.

[0098] Through the above steps, the system provides a highly stable laser source for precision spectral analysis, thereby improving the accuracy of gas detection.

[0099] Application Scenario 2: Quantum optics experiments (such as quantum key distribution systems)

[0100] In quantum optics, this laser is used to generate highly coherent single-photon sources to support quantum key distribution (QKD). It ensures mode stability of entangled photon pairs by compensating for optical path perturbations through dynamic wavefront shaping.

[0101] Step 1: System Preparation. Integrate the laser onto the quantum optics rig. Connect the semiconductor laser gain module to the pump optical path. Place the adaptive optics modulator of the dynamic wavefront shaping module in front of the nonlinear crystal (such as periodically polarized lithium niobate). Connect the wavefront detection unit to the control system. Ensure single-mode pumping with the single-mode screening module. Couple the laser output module to the photon detector. Integrate the decision unit of the high-precision closed-loop control module to fuse quantum noise data.

[0102] Step 2: Parameter Setting. Set the pump wavelength (e.g., 780nm, for rubidium atom transitions), and input the environmental disturbance threshold through the central processing unit; set the chip temperature (20°C) through the temperature control unit, and set the drive current (50mA) through the current control unit; initialize the adaptive algorithm circuit parameters through the wavefront feedback control unit, and activate the photoelectric feedback loop through the quantum noise compression component of the noise suppression unit; set the side-mode suppression threshold through the power stability control unit.

[0103] Step 3: Real-time Operation. When the laser is working, the quantum well structure gain chip generates laser light, which is initially single-mode oriented through a distributed feedback grating and surface plasmon structure. The beam enters the dynamic wavefront shaping module, is collimated by the aspherical lens group, and the wavefront detection unit collects information, transmitting it to the signal processor to convert and compensate the signal. This compensates for vibration distortion by adjusting the pixel array of the liquid crystal spatial light modulator. The hybrid structure of the single-mode screening module further filters the beam. The temperature control unit adjusts the thermoelectric cooler through a closed-loop adjustment using a fiber Bragg grating sensor and optical demodulation circuit. The adaptive filter monitoring feedback loop of the current control unit generates corrections. The spectral line monitoring function of the power stability control unit analyzes information through a spectral analysis circuit, and the central processing unit generates an optimization signal to adjust the piezoelectric element of the resonant cavity tuner to change the cavity length. The central processing unit collects data, processes the wavefront image through the accelerator in the graphics processing unit, and generates coordination commands that are transmitted to each unit.

[0104] Step 4: Output Application. A stable laser-pumped nonlinear crystal generates entangled photon pairs, which are then blocked from reflection by an optical isolator. The photon pairs are distributed to a communication link, and the QKD system encodes the key for secure transmission. The system compensates for path disturbances to ensure entanglement fidelity >95%.

[0105] Through the above steps, the system provides a reliable light source in quantum optics experiments and supports highly secure communication.

[0106] Application Scenario 3: Laser precision processing (such as micro / nano structure etching)

[0107] In laser precision machining, this laser is used for high-precision material processing (such as etching of silicon wafer microstructures). The control system provides real-time stable output, compensates for mechanical vibration, and ensures a stable focus.

[0108] Step 1: System Preparation. Fix the laser on the machine tool, align the semiconductor laser gain module with the focusing lens, and place the dynamic wavefront shaping module in the optical path; connect the single-mode screening module to the output; connect the adaptive fiber coupler of the laser output module to the processing head; connect the high-precision closed-loop control module to the vibration sensor, and monitor environmental disturbances with the central processing unit.

[0109] Step 2: Parameter Setting. Set the processing wavelength (e.g., 1064nm for infrared etching), input the power target (10mW) and temperature threshold through the integrated decision unit; set the constant current source in the current control unit; prepare the compensation in the adaptive algorithm circuit of the wavefront feedback control unit; the noise suppression unit is integrated in the signal path.

[0110] Step 3: Real-time Operation. The gain chip generates a beam, which is enhanced by a surface plasmon structure; the beam shaping submodule collimates the beam; the wavefront detection unit acquires the distortion, the digital signal processor performs filtering and compensation calculations, and adjusts the adaptive optics modulator; the single-mode screening module filters the beam; the temperature control unit adjusts the driver in a closed loop; the current control unit generates a correction signal; the power stabilization control unit acquires spectral lines and generates an adjustment signal; the central processing unit fuses the data and generates instructions through a multi-core processor to coordinate the entire system.

[0111] Step 4: Application. A stable laser is focused onto the material surface, and reflection is isolated by a magneto-optical crystal; the processing head scans and etches the microstructure, and the system compensates for vibration to ensure a linewidth of <1μm, for use in semiconductor chip manufacturing.

[0112] Through the above steps, the system improves machining accuracy in precision machining. Specific Implementation Example 7:

[0114] like Figures 1 to 3 As shown, this embodiment provides a description of the operating environment for a highly stable single-mode semiconductor laser and its control system based on dynamic wavefront shaping. The system is designed as an embedded real-time application, running on a high-performance hardware platform, supporting hardware acceleration and development platform APIs, ensuring a response time of less than 1 millisecond under complex disturbances, and achieving highly stable single-mode output. The following details the operating environment configuration, hardware acceleration mechanism, and development platform API integration, and demonstrates its real-time performance and feasibility through logical reasoning and existing technical evidence. The environment is based on a standard industrial embedded system, compatible with laboratory prototypes and commercial deployments, avoiding reliance on immature technologies.

[0115] runtime environment configuration:

[0116] The system runs on an embedded computing platform, such as an ARM-based single-board computer (e.g., NVIDIA Jetson series or Raspberry Pi Compute Module extension), combined with a dedicated hardware accelerator. The core processor uses a multi-core ARM Cortex-A series (e.g., quad-core or octa-core, operating at 1.5-2.5GHz), with 4-16GB of LPDDR4 RAM and eMMC or NVMe SSD storage (64GB or more). The operating system is a real-time Linux kernel (e.g., a patched version of PREEMPT_RT) or an RTOS (e.g., FreeRTOS) to ensure task scheduling priority and low jitter. External interfaces include USB 3.0 for data transfer, GPIO for sensor connections, and PCIe for expansion accelerator cards. The power supply is a stable 5-12V DC input, supporting an industrial-grade temperature range (-20°C to +60°C) to ensure stable operation in laboratory or field environments. Laser hardware (e.g., gain chip and modulator) is integrated into the platform via a custom PCB board. The control system software is written in C / C++, combined with Python scripts for prototype debugging.

[0117] Hardware acceleration mechanisms:

[0118] To achieve real-time wavefront shaping and closed-loop control, the system employs dual hardware acceleration via FPGA and GPU.

[0119] FPGA acceleration: Field programmable gate arrays (such as Xilinx Zynq series or Intel Cyclone V, with 50K-200K logic cells) are used to process high-frequency signals and low-latency tasks. Specifically, the adaptive algorithm circuitry and signal processor of the wavefront feedback control unit are integrated on the FPGA, processing the phase and amplitude information acquired by the wavefront detection unit through a parallel pipeline architecture. The digital signal processor module implements filtering and compensation calculations in the FPGA, using hardware multipliers and LUTs (lookup tables) to accelerate the operation; the processing circuitry of the power stabilization control unit (such as the operational amplifier analog section) is digitized through the mixed-signal IP core of the FPGA to achieve spectral line analysis. The FPGA is connected to the central processing unit via an AXI bus, with a data transmission delay of <100μs. The photoelectric feedback loop of the noise suppression unit is implemented in hardware loop form in the FPGA to ensure the real-time response of the quantum noise compression component.

[0120] GPU acceleration: Embedded GPUs (such as NVIDIA Tegra series integrated GPUs with CUDA cores 128-512) are used to process image computations and parallel computing tasks on wavefront phase data. The graphics processing unit accelerator accelerates multi-core processor data fusion in the central processing unit through the CUDA library, for example, performing batch matrix operations on acquired temperature, current, wavefront phase, and output power data. The GPU shares memory with the host, reducing data copy overhead and enabling parallel processing for wavefront reconstruction.

[0121] This dual-acceleration mechanism logically meets the system requirements: the FPGA processes low-level real-time signals (high-frequency sampling rate > 10kHz), while the GPU processes medium-level computationally intensive tasks (such as multi-sensor fusion), ensuring overall system load balance.

[0122] Development platform API integration:

[0123] The system development uses standard APIs and toolchains to ensure compatibility and portability.

[0124] FPGA Development API: Employing the Xilinx Vivado or AMD Vitis toolchain, it provides HDL (Verilog / VHDL) descriptions for adaptive algorithm circuits and feedback loops. The API includes an AXI Stream interface for data stream transmission and Vivado IPIntegrator for module integration (such as ADC IP cores for analog-to-digital converter circuits). Real-time performance is verified using Vivado's timing analysis tools, ensuring computation is completed within a clock cycle (typical clock frequency 100-200MHz).

[0125] GPU Development API: Utilizing the NVIDIA CUDA Toolkit (version 12.x or later), it provides the cuBLAS library for accelerating matrix operations (such as wavefront compensation calculations) and the cuFFT library for processing spectral information. The API is integrated into the central processing unit software, generating executable files through the nvcc compiler, and supports parallel thread blocks (block size 256-1024) for processing wavefront pixel array data.

[0126] Embedded platform APIs: The operating system level uses POSIX APIs (such as pthread for multithreading) and libusb for sensor interfaces; control system steps (such as SP1-SP6) are prioritized and scheduled via FreeRTOS task queues. Data buses (such as I2C / SPI) use Linux device driver APIs to ensure non-blocking instruction transmission between temperature and current control units.

[0127] These APIs are based on mature open-source / commercial frameworks, and the development cycle is controllable (3-6 months for prototypes).

[0128] Real-time proof:

[0129] The real-time performance of the system is defined as an end-to-end delay of <1ms from wavefront disturbance detection to compensation completion, with a sampling rate >1kHz, based on the following logic and criteria:

[0130] Logical reasoning: After acquiring information, the wavefront detection unit transmits it to the FPGA via signal lines (delay <10μs, based on the AXI bus standard). The digital signal processor performs filtering (digital filtering operation, period <50μs) and compensation calculation (iterative solution, <200μs after FPGA parallelization). The compensation signal adjusts the liquid crystal spatial light modulator through the drive interface (response time <500μs, inherent characteristics of liquid crystal material). The multi-core processor of the central processing unit fuses the data (<300μs with GPU acceleration) and generates coordinated instruction transmission (bus delay <100μs). The total accumulated delay is <1ms, meeting real-time requirements.

[0131] Feasibility proof:

[0132] The feasibility of the system is based on technological maturity and similar applications:

[0133] Logical reasoning: Hardware components (such as quantum well chips and liquid crystal spatial light modulators) are all commercially available, mature products (e.g., provided by Thorlabs or Hamamatsu), and the control module uses a standard embedded platform, avoiding the high cost of custom ASICs. The development APIs (such as CUDA and Vivado) have a rich ecosystem, supporting rapid iteration. The modular system design allows for independent testing (e.g., verifying wavefront feedback first, then integrating the closed loop), resulting in low risk.

[0134] It should be noted that, in this document, relational terms such as "including" and "first" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising a reference structure" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0135] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A highly stable single-mode semiconductor laser based on dynamic wavefront shaping, characterized in that: It includes a semiconductor laser gain module, a dynamic wavefront shaping module, a single-mode screening module, and a laser output module, which are optically coupled in sequence, wherein: The semiconductor laser gain module is composed of a quantum well structure gain chip. The active region surface of the gain chip is integrated with a distributed feedback grating and a surface plasmon structure. The distributed feedback grating and the surface plasmon structure are combined on the active region surface through a surface etching process. The surface plasmon structure is composed of an array of metal nanoparticles and embedded in the periodic gaps of the distributed feedback grating. The dynamic wavefront shaping module consists of an adaptive optics modulator, a wavefront detection unit, and a beam shaping submodule. The beam shaping submodule is composed of an aspherical lens group and is placed at the output end of the semiconductor laser gain module. The aspherical lens group collimates and shapes the diverging beam output from the semiconductor laser gain module into a Gaussian beam before it is incident on the adaptive optics modulator. The wavefront detection unit is composed of an integrated focal plane array sensor and is placed in the output optical path of the adaptive optics modulator. The integrated focal plane array sensor collects the laser wavefront phase and amplitude information after being shaped by the adaptive optics modulator and transmits it to the control system via a data line. The adaptive optics modulator is composed of a liquid crystal spatial light modulator and is placed between the beam shaping submodule and the single-mode screening module. The liquid crystal spatial light modulator adjusts the laser wavefront phase distribution through a pixel array. The single-mode screening module is composed of a hybrid structure of an integrated photonic crystal grating and a ring resonant cavity. The integrated photonic crystal grating is embedded in the cavity wall of the ring resonant cavity and coupled to the optical path of the ring resonant cavity through a photonic crystal aperture array. The laser output module consists of an adaptive fiber coupler and an optical isolator. The adaptive fiber coupler integrates a microelectromechanical system and is located at the output end of the single-mode screening module. The microelectromechanical system adjusts the coupling position through an actuator. The optical isolator is located at the output end of the adaptive fiber coupler and blocks reflected light through a magneto-optical crystal.

2. A control system for a highly stable single-mode semiconductor laser based on dynamic wavefront shaping as described in claim 1, characterized in that: The system includes a high-precision closed-loop control module electrically connected to the semiconductor laser gain module and dynamic wavefront shaping module of the laser. The high-precision closed-loop control module comprises a temperature control unit, a current control unit, and an integrated decision unit. The temperature control unit is connected to the gain chip of the semiconductor laser gain module via a thermal conductivity interface. The current control unit is connected to the gain chip via a wire. The integrated decision unit is connected to the temperature control unit and the current control unit via a data bus and fuses sensor data, including temperature signals, current signals, and wavefront information. The integrated decision unit is composed of a microprocessor chip and processes the fused data through internal algorithm circuitry to generate control commands. These control commands are transmitted to the temperature control unit and the current control unit via the data bus.

3. The control system according to claim 2, characterized in that: The high-precision closed-loop control module also includes a wavefront feedback control unit. The wavefront feedback control unit is connected to the wavefront detection unit of the dynamic wavefront shaping module via a signal line and to the adaptive optics modulator via a drive interface. The wavefront feedback control unit is composed of a signal processor and receives the phase and amplitude information collected by the wavefront detection unit. The signal processor is composed of an analog-to-digital conversion circuit and an arithmetic circuit and converts the phase and amplitude information into a compensation signal. The compensation signal is transmitted to the adaptive optics modulator via the drive interface, and the adaptive optics modulator adjusts the pixel array according to the compensation signal.

4. The control system according to claim 3, characterized in that: The high-precision closed-loop control module also includes a power stabilization control unit and a noise suppression unit. The power stabilization control unit is optically coupled to the laser output module through a photodetector and collects output power and spectral line information. The photodetector is composed of a photodiode array and converts the collected information into an electrical signal. The electrical signal is transmitted to the processing circuit of the power stabilization control unit through a feedback line. The processing circuit is composed of an operational amplifier and a filter and generates an adjustment signal. The adjustment signal is transmitted to the current control unit and the wavefront feedback control unit through a control line. The noise suppression unit is composed of a noise compression circuit and integrated into the signal path of the high-precision closed-loop control module. The noise compression circuit is composed of a quantum noise compression component and is connected to the noise source through a photoelectric feedback loop.

5. The control system according to claim 4, characterized in that: The temperature control unit consists of a combination of a thermoelectric cooler and an integrated fiber Bragg grating temperature sensor. The thermoelectric cooler is in contact with the substrate of the gain chip through a Peltier effect element. The integrated fiber Bragg grating temperature sensor is embedded in the heat transfer path of the thermoelectric cooler and connected to a signal processor through an optical fiber. The signal processor consists of an optical demodulation circuit and converts temperature changes into electrical signals. The electrical signals are transmitted to the driver of the thermoelectric cooler through a closed-loop circuit. The driver consists of a power amplifier and adjusts the current direction of the thermoelectric cooler.

6. The control system according to claim 5, characterized in that: The current control unit consists of a laser diode driver and an active noise cancellation circuit. The laser diode driver is composed of a constant current source circuit and is connected to the electrodes of the gain chip via wires. The active noise cancellation circuit consists of an adaptive filter and an electromagnetic compatibility shielding structure. The adaptive filter is placed at the output of the constant current source circuit and monitors current fluctuations through a feedback loop. The feedback loop consists of a sampling resistor and a comparator and generates a correction signal. The correction signal is transmitted to the adjustment module of the adaptive filter through internal circuitry. The electromagnetic compatibility shielding structure consists of a metal shell surrounding the entire current control unit and is grounded.

7. The control system according to claim 3, characterized in that: The wavefront feedback control unit is composed of an adaptive algorithm circuit, which is composed of a digital signal processor and integrated on the main board of the wavefront feedback control unit. The digital signal processor receives phase and amplitude information through an input interface and performs algorithm calculations. The algorithm calculations include filtering and compensation calculations. The compensation calculation results are transmitted to the adaptive optical modulator through an output interface. The adaptive optical modulator adjusts the voltage distribution of the liquid crystal pixels according to the compensation calculation results. The voltage distribution is phase-adjusted through a driving array.

8. The control system according to claim 4, characterized in that: The power stabilization control unit integrates a spectral line monitoring function, which consists of a spectral analysis circuit connected to a photodetector. The spectral analysis circuit consists of a spectrometer and a detection array and analyzes spectral line information. The spectral line information is transmitted to the central processing unit of the power stabilization control unit via a data line. The central processing unit consists of a microcontroller and generates an optimization signal. The optimization signal is transmitted to the resonant cavity adjuster of the single-mode screening module via a control bus. The resonant cavity adjuster consists of a piezoelectric element and changes the cavity length of the ring resonant cavity.

9. The control system according to claim 6, characterized in that: The high-precision closed-loop control module consists of a central processing unit, which is composed of a multi-core processor and an integrated graphics processing unit accelerator. It collects temperature, current, wavefront phase, output power, and environmental disturbance data through a bus interface. The bus interface includes an analog-to-digital converter and a multiplexer. The multi-core processor processes the collected data through parallel computing and generates coordination instructions. The coordination instructions are transmitted to the temperature control unit, current control unit, wavefront feedback control unit, and power stabilization control unit through the output port. The graphics processing unit accelerator is composed of a graphics processing chip and performs image processing on the wavefront phase data.

10. The control system according to claim 9, characterized in that: The control system is used to implement the following steps: Sp1 connects to the gain chip of the semiconductor laser gain module through the temperature control unit, collects temperature signals and adjusts the current direction of the thermoelectric cooler to regulate the temperature of the gain chip; Sp2 connects to the gain chip via the current control unit, acquires the current signal, and generates a correction signal through the active noise cancellation circuit to adjust the drive current. Sp3: The laser wavefront phase and amplitude information after being shaped by the adaptive optic modulator is acquired by the wavefront detection unit and transmitted to the wavefront feedback control unit through the signal line. Sp4, the wavefront feedback control unit receives phase and amplitude information, converts it into a compensation signal through a digital signal processor, and transmits it to the adaptive optics modulator through the drive interface to adjust the pixel array; Sp5: The photodetector of the power stabilization control unit collects the output power and spectral information of the laser output module, and generates an adjustment signal that is transmitted to the current control unit and the wavefront feedback control unit. The SP6 central processing unit collects temperature, current, wavefront phase, output power, and environmental disturbance data through a bus interface. It processes the data through a multi-core processor and generates coordination instructions, which are then transmitted to the temperature control unit, current control unit, wavefront feedback control unit, and power stabilization control unit to achieve closed-loop feedback adjustment of the laser output wavefront and stability.

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