Fiber laser power quantum control device, method, laser emitting apparatus

Abstract

The present specification discloses a kind of optical fiber type laser power quantum control device, method, laser emitting equipment, to improve the anti-interference ability and stability of laser power.The device of the present application comprises: first branch, configured to the laser output by laser, output 0 order diffraction light after passing through acoustooptic modulator, output the power laser to be stabilized after passing through optical fiber isolator;Second branch is feedback adjustment branch, the power laser to be stabilized in first branch is used as monitoring signal, is introduced into atomic clock, so that the output frequency of atomic clock changes, based on the deviation between the output frequency and given output frequency, the polarization state of laser in first branch is adjusted by feedback control method, to stabilize the power of output laser.In the present application, the quantum control device using all-fiber structure has the advantages of simple structure, small size, low cost, light weight, low difficulty of experimental device, free from debugging space optical path, not easy to be affected by external stray light, and improves the stability of laser power.

Description

Technical Field

[0001] This document relates to the field of optoelectronic technology, and in particular to a fiber-optic laser power quantum control device, method, and laser emitting equipment. Background Technology

[0002] Lasers are core components of quantum sensors such as atomic clocks and atomic interferometers. As the requirements for quantum sensor performance continue to increase in scientific research and production, higher demands are being placed on the precise measurement and long-term stable control of laser power.

[0003] Current methods for quantum measurement and stable control of laser power involve modulating the laser signal from the laser source using a spatial acousto-optic modulator. The output signal of the acousto-optic modulator is then coupled into a rubidium atomic gas chamber via a spatial optical path. The power of the diffracted light output from the acousto-optic modulator is controlled by feedback based on changes in the output frequency of the rubidium atomic clock. However, this method suffers from several drawbacks. The spatial optical path is susceptible to interference from external light sources, and the experimental system requires collimation and coupling, demanding a certain level of expertise from the operators in setting up the spatial optical path. Furthermore, the collimation efficiency of the spatial optical path and the diffraction efficiency of the acousto-optic modulator also affect the stable control of the laser power. In addition, the cost of setting up a spatial optical path experimental setup is relatively high.

[0004] Therefore, improving the anti-interference capability and stability of laser power while saving costs and reducing the difficulty of experimental setup is an important and urgent problem to be solved. Summary of the Invention

[0005] To improve the anti-interference capability and stability of laser power, one aspect of the present invention proposes a fiber-optic laser power quantum control device, including a first branch and a second branch;

[0006] The first branch is configured to output the 0th order diffracted light from the laser output by the laser through an acousto-optic modulator, and then output the laser with the power to be stabilized after passing through an optical fiber isolator.

[0007] The second branch is a feedback adjustment branch. The power laser to be stabilized output from the first branch after passing through the fiber optic isolator is used as a monitoring signal and introduced into the atomic clock to change its output frequency. Based on the deviation between the output frequency and the given output frequency, the diffraction efficiency of the acousto-optic modulator in the first branch is adjusted through feedback control to stabilize the power of the output laser.

[0008] In some preferred embodiments, the first branch includes an acousto-optic modulator, an optical fiber isolator, and a beam splitter;

[0009] The acousto-optic modulator is configured to control the power of the laser beam using an electronic drive signal;

[0010] The fiber optic isolator is configured to use the Faraday effect of a magneto-optical crystal to isolate reflected light, allowing light to propagate in only one direction.

[0011] The beam splitter is configured to split the laser beam output after passing through the fiber optic isolator into two beams.

[0012] In some preferred embodiments, the acousto-optic modulator is an optical fiber acousto-optic modulator.

[0013] In some preferred embodiments, the beam splitter is an optical fiber coupler.

[0014] In some preferred embodiments, the second branch includes an atomic clock, a frequency counter, a feedback control unit, and a signal generator;

[0015] The atomic clock is configured to change its output frequency based on one of the laser beams split by the imported beam splitting device.

[0016] The frequency counter is configured to collect the output frequency information of the atomic clock;

[0017] The feedback control unit is configured to acquire the frequency information collected by the frequency counter, obtain the deviation between the frequency and the given output frequency, and generate the adjustment amount of the acousto-optic modulator.

[0018] The signal generator is configured to adjust the driving power used to change the diffraction efficiency of the acousto-optic modulator based on the adjustment amount of the acousto-optic modulator.

[0019] In some preferred embodiments, the feedback control unit is a PID feedback control unit.

[0020] In some preferred embodiments, an optical fiber is provided between the laser and the acousto-optic modulator; the laser output from the laser is transmitted to the acousto-optic modulator through the optical fiber.

[0021] A second aspect of the present invention provides a fiber-optic laser power quantum control method, based on the aforementioned fiber-optic laser power quantum control device, the method comprising:

[0022] The laser output from the laser is processed by an acousto-optic modulator according to preset values, and the output is 0th order diffracted light.

[0023] The output laser after passing through the fiber optic isolator is split into beams by a beam splitter, with the first beam used for output and the second beam used for power monitoring.

[0024] The second laser beam is introduced into the atomic clock, causing the output frequency of the atomic clock to change accordingly. Based on the deviation between this output frequency and the given output frequency, the diffraction efficiency of the acousto-optic modulator in the first branch is adjusted through a feedback control method to stabilize the output laser power.

[0025] In some preferred embodiments, the feedback control method is a PID feedback control method.

[0026] In a third aspect, the present invention provides a power-stable laser emitting device, characterized in that it includes a laser and the aforementioned fiber-optic laser power quantum control device.

[0027] The above-described at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0028] This invention solves the problem of low power stability caused by external environmental interference in extracavity laser power control, as well as the problem of high requirements for optical path collimation and coupling efficiency. It reduces the difficulty of experimental setup, improves the system's integrability, and saves experimental costs. The quantum control device using an all-fiber structure in this invention has the advantages of simple structure, small size, low cost, light weight, low experimental setup difficulty, no need to adjust the spatial optical path, and less susceptible to external stray light, and also improves laser power stability. Attached Figure Description

[0029] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0030] Figure 1 A schematic diagram of a fiber-optic laser power quantum control device provided in one embodiment of this specification;

[0031] Figure 2 A schematic diagram of a fiber-optic laser power quantum control device provided for another embodiment of this specification;

[0032] Figure 3 This is a schematic diagram of a fiber-optic laser power quantum control method provided in one embodiment of this specification. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0034] The technical solutions provided by the various embodiments of this application are described in detail below with reference to the accompanying drawings.

[0035] This invention uses optical fibers, acousto-optic modulators, and optical fiber isolators to construct a laser power adjustment branch. The laser power is controlled through an all-fiber structure. At the same time, an atomic clock and a feedback control unit are used to form a closed-loop control circuit for the laser power, thereby simplifying the structure, reducing the size, lowering the cost, reducing the weight, and reducing the difficulty of the experimental device. It also eliminates the need to adjust the spatial optical path, is less susceptible to the influence of external stray light, and improves the stability of the laser power.

[0036] An acousto-optic modulator is a device that uses electronic drive signals to control the power, frequency, or spatial direction of a laser beam. It utilizes the acousto-optic effect, that is, changing the refractive index through the mechanical oscillation pressure of acoustic waves.

[0037] An atomic clock is a device that uses the electromagnetic waves emitted when atoms absorb or release energy to keep time. It is the most accurate known time measurement and frequency standard in the world, with high stability; currently reported long-term stability of atomic clocks reaches the order of 10⁻¹⁶. When atomic energy levels are affected by external near-resonant pump light, energy level shifts occur. The amount of shift is related to the frequency and intensity of the pump light, causing a change in the atomic clock's output frequency. Therefore, changes in the atomic clock's output frequency can reflect changes in the laser power introduced into the atomic clock.

[0038] Figure 1 This specification provides a schematic diagram of a fiber-optic laser power quantum control device according to an embodiment. The device may specifically include a first branch and a second branch. The first branch is configured to output 0th-order diffracted light from the laser output by the laser source via an acousto-optic modulator, and then output a laser of a desired power after passing through an optical fiber isolator. The second branch is a feedback adjustment branch, which uses the laser of the desired power output from the first branch after passing through the optical fiber isolator as a monitoring signal, inputting it into an atomic clock to change its output frequency. Based on the deviation between this output frequency and a given output frequency, the diffraction efficiency of the acousto-optic modulator in the first branch is adjusted through a feedback control method to stabilize the output laser power.

[0039] To provide a detailed description of the fiber-optic laser power quantum control device of the present invention, the following is in conjunction with... Figure 2The specific structure of the device of the present invention will be described in detail below. The fiber-optic laser power quantum control device in this embodiment includes an acousto-optic modulator, a fiber optic isolator, a beam splitter, an atomic clock, a frequency counter, a feedback control unit, and a signal generator; the first branch consisting of the acousto-optic modulator, the fiber optic isolator, and the beam splitter forms a closed-loop control with the second branch consisting of the atomic clock, the frequency counter, the feedback control unit, and the signal generator to stabilize the output laser power.

[0040] An acousto-optic modulator is configured to control the power of a laser beam using electronic drive signals. It utilizes the acousto-optic effect, that is, changing the refractive index through acoustic mechanical oscillation pressure, thereby controlling the power of the laser beam. In this embodiment, the acousto-optic modulator is a fiber-optic modulator, the laser is a 795nm laser, and an optical fiber for transmitting the laser is provided between the laser and the fiber-optic acousto-optic modulator.

[0041] Fiber optic isolators are configured to utilize the Faraday effect of magneto-optical crystals to isolate reflected light, allowing light to propagate in only one direction. Fiber optic isolators are used to prevent light sources from being adversely affected by back reflections or signals; back reflections can damage lasers or cause mode hopping, amplitude variations, or frequency shifts. In high-power applications, back reflections can also cause instability and power spikes.

[0042] The beam splitter is configured to split the laser output after passing through the fiber optic isolator into two beams; one beam is used for output to meet actual needs, and the other beam is used for signal monitoring and coupled into the atomic clock in the feedback control unit. In this embodiment, the beam splitter is a fiber optic coupler.

[0043] An atomic clock is configured to change its output frequency based on one of the laser beams split by the aforementioned beam-splitting device. The change in the atomic clock's output frequency reflects the change in the laser power within the atomic clock.

[0044] A frequency counter is configured to collect the output frequency information of the atomic clock.

[0045] The feedback control unit is configured to acquire the frequency information collected by the frequency counter, obtain the deviation between the frequency information and the given output frequency, and generate the adjustment amount of the acousto-optic modulator. In this embodiment, the feedback control unit is a PID feedback control unit. The PID control unit outputs a signal to control the output power of the signal generator, thereby changing the diffraction efficiency of the acousto-optic modulator.

[0046] A signal generator is configured to generate a drive power control signal for the acousto-optic modulator based on the adjustment amount of the acousto-optic modulator. The signal generator is the driving power source for the fiber optic acousto-optic modulator. Changing the output power of the signal generator can change the diffraction efficiency of the fiber optic acousto-optic modulator, thereby changing the zero-order optical power output by the fiber optic acousto-optic modulator.

[0047] During operation, the laser output from the laser is transmitted through an optical fiber to a fiber-optic acousto-optic modulator. The fiber-optic acousto-optic modulator modulates the input laser, outputting zero-order diffracted light. The zero-order diffracted light is transmitted unidirectionally forward through an optical fiber isolator, preventing the laser in the optical fiber loop from returning to the laser and affecting its normal operation. The output end of the optical fiber isolator is connected to an optical fiber coupler, and the laser output from the optical fiber isolator is transmitted to the optical fiber coupler. The optical fiber coupler splits the input laser into two paths: one path is used to output a laser of stabilizing power for actual needs, and the other path is coupled into an atomic clock. The atomic clock changes its output frequency based on the laser beam split by the aforementioned beam splitting device. A frequency counter collects the atomic clock's output frequency information and transmits it to a feedback control unit. The feedback control unit calculates the deviation between the monitored atomic clock output frequency information and the given output frequency, processes it through a PID feedback control algorithm, and outputs an error compensation signal as the control signal for the fiber-optic acousto-optic modulator. This signal is sent to a signal generator to control the driving power of the fiber-optic acousto-optic modulator, achieving stable power control.

[0048] A second embodiment of the present invention provides a fiber-optic laser power quantum control method, based on the aforementioned fiber-optic laser power quantum control device, the method as follows: Figure 3 As shown, the process includes: the laser output from the laser source is processed according to a preset value, and then the laser output is diffracted into 0th order light by an acousto-optic modulator; the output laser after passing through an optical fiber isolator is split into beams by a beam splitter, wherein the first beam is used for output and the second beam is used for power monitoring; the second beam is guided into an atomic clock, causing the output frequency of the atomic clock to change accordingly; based on the deviation between the output frequency and the given output frequency, the diffraction efficiency of the acousto-optic modulator in the first branch is adjusted by a feedback control method to stabilize the power of the output laser.

[0049] In this embodiment, the feedback control method is the PID feedback control method.

[0050] A laser emitting device according to a third embodiment of the present invention includes a laser and the aforementioned fiber-optic laser power quantum control device.

[0051] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process and related descriptions of the fiber-optic laser power quantum control method and laser emitting device described above can be found in the corresponding content of the aforementioned fiber-optic laser power quantum control device embodiments, and will not be repeated here.

[0052] Specifically, according to embodiments of this disclosure, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication component, and / or installed from a removable medium. When the computer program is executed by a central processing unit (CPU), it performs the functions defined in the methods of this application. It should be noted that the computer-readable medium described above in this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in connection with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on a computer-readable medium can be transmitted using any suitable medium, including but not limited to: wireless, wire, optical fiber, RF, etc., or any suitable combination thereof.

[0053] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0054] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0055] The terms “first”, “second”, etc., are used to distinguish similar objects, not to describe or indicate a specific order or sequence.

[0056] The term "comprising" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent in such process, method, article, or apparatus / device.

[0057] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the above description is merely an embodiment of this application and is not intended to limit the application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the scope of the claims of this application.

Claims

1. A fiber-optic laser power quantum control device, characterized in that, Including the first branch road and the second branch road; The first branch is configured to output the 0th order diffracted light from the laser output by the laser through an acousto-optic modulator, and then output the laser of the power to be stabilized after passing through an optical fiber isolator. The second branch is a feedback adjustment branch. The power laser to be stabilized output from the first branch after passing through the fiber optic isolator is used as a monitoring signal and introduced into the atomic clock to change its output frequency. Based on the deviation between the output frequency and the given output frequency, the diffraction efficiency of the acousto-optic modulator in the first branch is adjusted by the feedback control method to stabilize the power of the output laser. in, The first branch includes an acousto-optic modulator, an optical fiber isolator, and a beam splitter; The acousto-optic modulator is configured to control the power of the laser beam using an electronic drive signal; The fiber optic isolator is configured to use the Faraday effect of a magneto-optical crystal to isolate reflected light, allowing light to propagate in only one direction. The beam splitter is configured to split the laser beam output after passing through the fiber optic isolator into two beams; The acousto-optic modulator is an optical fiber acousto-optic modulator; The beam splitter is an optical fiber coupler; The second branch includes an atomic clock, a frequency counter, a feedback control unit, and a signal generator; The atomic clock is configured to change its output frequency based on one of the laser beams split by the imported beam splitting device. The frequency counter is configured to collect the output frequency information of the atomic clock; The feedback control unit is configured to acquire the frequency information collected by the frequency counter, obtain the deviation between the frequency and the given output frequency, and generate the adjustment amount of the acousto-optic modulator. The signal generator is configured to adjust the driving power used to change the diffraction efficiency of the acousto-optic modulator based on the adjustment amount of the acousto-optic modulator. The feedback control unit is a PID feedback control unit; An optical fiber is provided between the laser and the acousto-optic modulator; the laser output from the laser is transmitted to the acousto-optic modulator through the optical fiber.

2. A method for quantum control of fiber optic laser power, characterized in that, Based on the fiber-optic laser power quantum control device according to claim 1, the method includes: The laser output from the laser is modulated by acousto-optic modulation according to preset values ​​to output 0th order diffraction light; The output laser after passing through the fiber optic isolator is split into beams by a beam splitter, with the first beam used for output and the second beam used for power monitoring. The second laser beam is introduced into the atomic clock, causing the output frequency of the atomic clock to change accordingly. Based on the deviation between this output frequency and the given output frequency, the diffraction efficiency of the acousto-optic modulation in the first branch is adjusted through a feedback control method to stabilize the power of the output laser.

3. A laser emitting device, characterized in that, It includes a laser and the fiber-optic laser power quantum control device as described in claim 1.

Images