Cooperative regulation and control method for bandwidth and nonlinear performance of quantum dot laser

Abstract

The invention provides a quantum dot laser, and a quantum dot laser bandwidth and nonlinear performance coordinated regulation and control method, device and equipment. The method comprises the following steps: constructing the quantum dot laser into a nonlinear resonant subsystem driven by bias current; applying a bias current to the quantum dot laser; the quantum dot laser is set at a cooperative bias working point by regulating and controlling the magnitude of the bias current, and the cooperative bias working point is configured to cooperatively improve the relaxation oscillation frequency of the laser and control the nonlinear effect.

Description

Technical Field

[0001] This disclosure relates to the field of optoelectronic device technology, specifically to a quantum dot laser and a method, apparatus, and device for synergistic control of the bandwidth and nonlinear performance of the quantum dot laser. Background Technology

[0002] Quantum dot lasers, as a new generation of semiconductor laser sources, exhibit superior performance advantages due to their unique three-dimensional quantum confinement effect. Their core advantage lies in their extremely strong nonlinear optical properties. Based on a discrete atomic energy level structure, quantum dot lasers exhibit easily saturated gain, a large nonlinear refractive index change, and effectively suppressed relaxation oscillations. This makes them irreplaceable in applications such as all-optical signal processing (e.g., optical bistable states, wavelength conversion), high-speed direct modulation, and passive mode-locking for generating ultrashort pulses. However, limited by their low point state density distribution, traditional quantum dot lasers typically suffer from an inherent disadvantage of narrow gain bandwidth, which to some extent restricts their further application in ultrawideband tunable lasers, supercontinuum generation, and high-speed communication systems requiring extremely high bandwidth. Summary of the Invention

[0003] (a) Technical problems to be solved

[0004] In view of the above problems, this disclosure provides a quantum dot laser and a method, apparatus and device for synergistic control of the bandwidth and nonlinear performance of the quantum dot laser, so as to at least solve the technical problem of the inherent contradiction between gain bandwidth and nonlinear optical properties in quantum dot materials.

[0005] (II) Technical Solution

[0006] The first aspect of this disclosure provides a method for synergistically controlling the bandwidth and nonlinear performance of a quantum dot laser, comprising: constructing the quantum dot laser as a nonlinear resonator system driven by a bias current; applying a bias current to the quantum dot laser; and setting the quantum dot laser at a synergistic bias operating point by adjusting the magnitude of the bias current, wherein the synergistic bias operating point is configured to synergistically increase the relaxation oscillation frequency of the laser and control the nonlinear effect.

[0007] According to embodiments of this disclosure, setting the quantum dot laser to a cooperative bias operating point by adjusting the magnitude of the bias current includes: adjusting the bias current to a target bias current value, such that the relaxation oscillation frequency of the quantum dot laser is greater than or equal to a preset bandwidth threshold; and limiting the nonlinear distortion generated by the quantum dot laser to a preset application tolerance range, or, making the quantum dot laser operate in a preset nonlinear dynamic region.

[0008] According to embodiments of this disclosure, the cooperative bias operating point is the bias current point where the ratio of the relaxation oscillation frequency to the nonlinear distortion of the quantum dot laser reaches a local maximum.

[0009] According to embodiments of this disclosure, applying a bias current to the quantum dot laser includes: electrically pumping the quantum dot laser by applying a bias current to inject energy into the nonlinear resonator system.

[0010] According to an embodiment of this disclosure, the quantum dot laser includes a monolithically integrated quantum dot laser region and a modulation region. The method further includes: receiving a continuous optical signal generated by the quantum dot laser region through the modulation region, and modulating the continuous optical signal to output an encoded continuous optical signal, wherein the quantum dot laser region is configured to operate at the cooperative bias operating point.

[0011] According to embodiments of this disclosure, the nonlinear resonator system includes an optical resonator cavity, which is composed of a distributed feedback grating.

[0012] According to embodiments of this disclosure, the intrinsic oscillation mode of the nonlinear resonator system is determined by the structure of the distributed feedback grating.

[0013] A second aspect of this disclosure provides a quantum dot laser configured to be driven by the method described above to operate at a cooperative bias operating point.

[0014] A third aspect of this disclosure provides a device for synergistically controlling the bandwidth and nonlinear performance of a quantum dot laser, comprising: a construction module for constructing the quantum dot laser as a nonlinear resonator system driven by a bias current; an application module for applying a bias current to the quantum dot laser; and a control module for setting the quantum dot laser to a synergistic bias operating point by controlling the magnitude of the bias current, wherein the synergistic bias operating point is configured to synergistically increase the relaxation oscillation frequency of the laser and control nonlinear effects.

[0015] A fourth aspect of this disclosure provides an electronic device comprising: one or more processors; and a memory for storing one or more computer programs, wherein the one or more processors execute the one or more computer programs to implement the steps of the method described above.

[0016] (III) Beneficial Effects

[0017] This disclosure overcomes the shortcomings of the prior art and provides a method, device, apparatus, and medium for synergistic control of the bandwidth and nonlinear performance of quantum dot lasers. By making trade-offs to control the discrete energy levels and carrier dynamics of quantum dots, a completely new control dimension is introduced. The bias current acts as an "accelerator switch" to provide energy to this new dimension, thereby effectively expanding the optical gain bandwidth while maintaining the high-intensity nonlinear advantage of quantum dot lasers. Attached Figure Description

[0018] To gain a more complete understanding of this disclosure and its advantages, reference will now be made to the following description taken in conjunction with the accompanying drawings, wherein:

[0019] Figure 1 A flowchart illustrating the method for synergistic control of bandwidth and nonlinear performance of a quantum dot laser provided in an embodiment of this disclosure is shown.

[0020] Figure 2 The flowchart illustrates the process of the method for synergistic control of bandwidth and nonlinear performance of quantum dot lasers provided in the embodiments of this disclosure.

[0021] Figure 3 A schematic diagram of the structure of a quantum dot laser provided in an embodiment of this disclosure is shown.

[0022] Figure 4 This schematically illustrates a structural block diagram of a device for synergistic control of bandwidth and nonlinear performance of a quantum dot laser provided in an embodiment of the present disclosure.

[0023] Figure 5 The schematic diagram illustrates the hardware structure of an electronic device provided in an embodiment of this disclosure. Detailed Implementation

[0024] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0025] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0026] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0027] The accompanying drawings show some block diagrams and / or flowcharts. It should be understood that some blocks or combinations thereof in the block diagrams and / or flowcharts can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when executed by the processor, these instructions can create means for implementing the functions / operations described in these block diagrams and / or flowcharts.

[0028] Research has revealed that the bandwidth and nonlinear characteristics of quantum dot lasers are both rooted in their three-dimensional quantum confinement effect, a fundamental physical phenomenon. The two are closely related but also inherently contradictory, which is mainly reflected in the following two aspects.

[0029] First, there is a fundamental conflict in the density of states distribution. The remarkable nonlinearity of quantum dots, such as easy saturation gain and huge nonlinear refractive index, stems from their discrete, atomic density of states (δ-function type). Electron-hole pairs are confined to discrete energy levels, and even small changes in carrier concentration can trigger dramatic, nonlinear changes in optical properties—this is the root of their nonlinear advantage. However, it is precisely this discrete, narrow density of states distribution that limits the energy range that can provide optical gain. The gain spectrum of each quantum dot group is very narrow, resulting in a limited intrinsic gain bandwidth for conventional quantum dot lasers. To obtain a large bandwidth, a continuous or quasi-continuous broad density of states distribution is required, which is the root of the bandwidth disadvantage.

[0030] Second, there is a conflict in the dynamic distribution of charge carriers. Strong nonlinear effects depend on the rapid occupation and localization of charge carriers in the ground state energy level of a single quantum dot. This localization effect is the basis for generating high differential gain, low linewidth enhancement factor, and suppressing relaxation oscillations, which is key to maintaining the nonlinear advantage. However, in order to extend the bandwidth, it is usually necessary to introduce non-uniform distributions of size, composition, or stress (i.e., larger size non-uniformity) to create multiple groups of quantum dots with different energy levels, allowing their gain spectra to be superimposed and merged into a wider continuous spectrum. This inevitably leads to the redistribution and transition of charge carriers between quantum dots of different sizes / energy levels to meet the demand for bandwidth extension.

[0031] Strong nonlinearity requires quantum dot energy levels to remain "pure" and "discrete," while "wide bandwidth" requires energy levels to be "fused" and "continuous." This is an inherent contradiction stemming from the material's own physical properties. Simply increasing size inhomogeneity to extend bandwidth will inevitably dilute the concentration of charge carriers at different energy levels, weakening their localization effect, thereby leading to a decrease in the intensity of the nonlinear optical response and a degradation of its properties.

[0032] The technical problem to be solved by the embodiments of this disclosure is: "How to overcome the inherent contradiction between gain bandwidth and nonlinear optical characteristics in quantum dot materials, that is, to effectively expand the optical gain bandwidth of lasers without sacrificing or even enhancing their inherent high-intensity nonlinear optical response." Specifically, the embodiments of this disclosure aim to solve the problem that is difficult to balance in the prior art: the traditional method of broadening the bandwidth by increasing the non-uniformity of quantum dot size will disperse the carrier distribution, weaken the gain saturation effect and nonlinear refractive index change, and lead to the degradation of nonlinear performance such as optical bistable and four-wave mixing; while pursuing the uniform and discrete energy levels required for strong nonlinearity, it is necessary to face the bottleneck of the available gain spectrum being too narrow, which makes it difficult to support broadband tuning, ultrashort pulse generation or high-speed high-capacity communication applications.

[0033] In view of this, the present disclosure provides a method for synergistic control of bandwidth and nonlinear performance of quantum dot lasers, breaking the traditional inverse relationship between the two and achieving parallel improvement of bandwidth and nonlinear performance.

[0034] Figure 1 The flowchart illustrates a method for synergistically controlling the bandwidth and nonlinear performance of a quantum dot laser according to an embodiment of this disclosure.

[0035] like Figure 1 As shown, the method for synergistic control of bandwidth and nonlinear performance of quantum dot lasers specifically includes operations S1-S3.

[0036] In operation S1, the quantum dot laser is constructed as a nonlinear resonator system driven by a bias current.

[0037] Quantum dot lasers, also known as quantum dot distributed Bragg feedback lasers (QD-DFB), are key devices used in next-generation high-speed optical communication and integrated all-optical chips.

[0038] In embodiments of this disclosure, the nonlinear resonator system includes an optical resonant cavity constructed from a distributed feedback (DFB) grating. The intrinsic oscillation modes of the nonlinear resonator system are determined by the structure of the DFB grating. Through specific design of the DFB grating, the system can be provided with intrinsic oscillation modes, i.e., the longitudinal modes of the laser. These longitudinal modes determine the center frequency and fundamental linewidth of the laser, and are important fundamental parameters for laser performance.

[0039] In operation S2, a bias current is applied to the quantum dot laser.

[0040] After the system is built, a bias current can be applied to the constructed quantum dot laser. As a key external factor driving the laser, the magnitude and characteristics of the bias current can directly affect the laser's operating state.

[0041] In operation S3, the quantum dot laser is set to a cooperative bias operating point by adjusting the magnitude of the bias current, wherein the cooperative bias operating point is configured to cooperatively increase the relaxation oscillation frequency of the laser and control nonlinear effects.

[0042] The role of the synergistic bias operating point is to synergistically increase the relaxation oscillation frequency of the laser and effectively control nonlinear effects. The relaxation oscillation frequency is an important indicator of the laser's dynamic response; a higher relaxation oscillation frequency means the laser can respond to changes in external signals more quickly, thereby improving the system's response speed and stability. Simultaneously, effective control of nonlinear effects can ensure the laser's high-intensity nonlinear optical response while avoiding performance instability caused by excessive nonlinear effects, achieving synergistic optimization of gain bandwidth and nonlinear performance.

[0043] The discrete energy levels of quantum dots result in extremely high differential gain and low linewidth enhancement factors. High differential gain means that only a small change in charge carriers can produce a large gain change, which helps to achieve higher relaxation oscillation frequencies (fr) at lower currents—the core benefit of increasing the bias current. However, in quantum dot lasers, the relaxation process of charge carriers from the excited state to the ground state may not keep up with the rate of consumption by stimulated emission, leading to carrier accumulation in the excited state. This phenomenon introduces additional nonlinear effects and kinetic instability by altering the gain and refractive index, ultimately degrading nonlinear performance. In other words, while increasing the bias current can improve fr (bandwidth benefit), it also amplifies all nonlinear terms (nonlinearity disadvantage), creating a fundamental conflict. To address this issue, embodiments of this disclosure compromise between the discrete energy levels and carrier dynamics of quantum dots, adding a new dimension.

[0044] It is understood that the lasers prepared by the synergistic modulation method of quantum dot laser bandwidth and nonlinear performance provided in the embodiments of this disclosure have excellent overall performance and are particularly suitable for the following scenarios: in next-generation high-speed optical communication systems, they have the advantages of low chirp and large bandwidth, making them suitable for data center interconnection and coherent communication; in integrated all-optical chips, they can be used as core nonlinear elements for on-chip optical switches, logic gates and wavelength converters; in broadband tunable lasers and frequency comb sources, they can provide compact light sources for high-precision spectral measurement, sensing and imaging.

[0045] Based on the above embodiments, in this embodiment, setting the quantum dot laser to a cooperative bias operating point by adjusting the magnitude of the bias current includes: adjusting the bias current to a target bias current value, so that the relaxation oscillation frequency of the quantum dot laser is greater than or equal to a preset bandwidth threshold; and limiting the nonlinear distortion generated by the quantum dot laser to a preset application tolerance range, or making the quantum dot laser operate in a preset nonlinear dynamic region.

[0046] Figure 2 The schematic diagram illustrates the workflow of the method for synergistic control of bandwidth and nonlinear performance of quantum dot lasers provided in embodiments of this disclosure.

[0047] like Figure 2 As shown, in the low-energy region, continuous-wave (cw) quantum dot lasers exhibit slow command (modulation) response and narrow bandwidth, but also possess very stable operation and high linearity. In other words, in this energy region, the laser's output signal is relatively stable with low nonlinear distortion, but its signal processing and transmission capabilities are relatively limited. When entering the high-energy region, the response speed of the quantum dot laser increases dramatically, becoming extremely sensitive to commands, and the bandwidth also increases sharply. However, this energy region is also accompanied by many nonlinear instabilities, such as gain saturation depletion, carrier heating, and severe mode competition, leading to relaxation oscillations and severe nonlinear distortion, affecting the laser's performance stability and signal quality. In the extremely high-energy region, although the laser's carrier motion includes all possible frequency components, the coherence and noise levels are insufficient to meet the communication requirements of low noise and good coherence, thus significantly limiting its practical applications.

[0048] The method for synergistically controlling the bandwidth and nonlinear performance of quantum dot lasers provided in this disclosure does not aim to completely avoid nonlinear effects during laser design. Instead, it manipulates and utilizes the trade-off between bandwidth and nonlinearity in quantum dot lasers. Through appropriate control methods, the bias current is adjusted to a target bias current value to determine the optimal bias point (synergistic bias operating point). On one hand, this bias point must be high enough so that the relaxation oscillation frequency of the quantum dot laser can meet the bandwidth requirements, i.e., greater than or equal to a preset bandwidth threshold, thereby ensuring that the laser has sufficient data transmission and processing capabilities. On the other hand, the bias point must be low enough so that nonlinear distortion (such as harmonic distortion, intermodulation distortion, etc.) can be controlled within an acceptable range for the application (i.e., a preset application tolerance range), or just enough to make the laser operate in a specific, controllable nonlinear dynamic region (such as stable periodic oscillation) to meet the needs of special application scenarios (such as optical chaotic secure communication, etc.).

[0049] Quantum dots possess unique physical properties, particularly high differential gain and a low alpha factor. High differential gain means that only a small carrier change requires a large gain change, which helps achieve high performance at lower currents; the low alpha factor helps reduce linewidth enhancement effects and improve laser stability. These unique characteristics make the "optimal window" (i.e., the bias current range that satisfies bandwidth and nonlinearity requirements) of quantum dot lasers wider and easier to access than that of conventional lasers. This is precisely where the enormous potential of quantum dot lasers as high-performance light sources lies, providing strong support for their widespread application in high-speed optical communication, integrated all-optical chips, and other fields.

[0050] Preferably, the cooperative bias operating point is the bias current point where the ratio of the relaxation oscillation frequency to the nonlinear distortion of the quantum dot laser reaches a local maximum.

[0051] By setting the bias current at this point, it is possible to control nonlinear distortion to the greatest extent while ensuring that the laser has sufficient bandwidth, thereby achieving the best synergy between bandwidth and nonlinear performance and further improving the overall performance of quantum dot lasers.

[0052] Based on the above embodiments, in this embodiment, applying a bias current to the quantum dot laser includes: electrically pumping the quantum dot laser by applying a bias current to inject energy into the nonlinear resonator system.

[0053] Electrical pumping is a common method that uses electrical energy to excite the working substance of a laser, causing it to reach a population inversion state. In quantum dot lasers, by rationally designing the circuit and selecting a suitable power supply, a bias current of a specific size and characteristics is applied to the laser. Electrons in the current gain energy under the influence of the electric field and interact with the working substance (quantum dots) in the laser, thereby achieving energy injection.

[0054] It is understandable that injecting energy into the system through an electric pump with a bias current is the driving force for maintaining population inversion and stimulated emission.

[0055] In embodiments of this disclosure, the quantum dot laser includes a monolithically integrated quantum dot laser region and a modulation region. The method further includes: receiving a continuous optical signal generated by the quantum dot laser region through the modulation region, and modulating the continuous optical signal to output an encoded continuous optical signal, wherein the quantum dot laser region is configured to operate at the cooperative bias operating point.

[0056] Figure 3 A schematic diagram of the structure of a quantum dot laser provided in an embodiment of this disclosure is shown.

[0057] like Figure 3 As shown, this quantum dot laser employs a "functional separation" design, assigning two core tasks to the most suitable components. Specifically, the quantum dot laser region is responsible for high-linearity light generation. Due to its unique physical structure and the setting of its cooperative bias operating point, the quantum dot laser region can stably generate continuous optical signals with low nonlinear distortion, thus providing a high-quality base optical signal for subsequent signal modulation and ensuring good fidelity of the modulated signal. The modulation region, on the other hand, can be used for high-speed optical modulation. It can quickly and accurately modulate the continuous optical signal received from the quantum dot laser region, loading information onto the optical signal according to different encoding requirements, thereby outputting the encoded continuous optical signal. In a nonlinear resonator system, the bandwidth is mainly controlled by the intracavity photon density and is positively correlated with the modulation current; while linearity depends on the stability of the carrier density, which has a specific optimal operating point on the modulation current, namely the target bias current value. The synergistic balance of system performance is reflected near the optimal value of the modulation current. In this region, the system utilizes high photon density to excite relaxation oscillation peaks, thereby expanding the bandwidth. On the other hand, it can maintain the carrier density in a sufficiently stable clamping state to achieve high linearity output, thus avoiding the fundamental physical root of bandwidth and nonlinearity in existing technologies (i.e., achieving gain and modulation by changing the carrier density in the same active region).

[0058] In embodiments of this disclosure, a quantum dot laser is also provided, which is configured to be driven by the aforementioned method for synergistic modulation of quantum dot laser bandwidth and nonlinear performance to operate at a synergistic bias operating point. Figure 4 The schematic diagram illustrates the structural block diagram of the device for synergistic control of bandwidth and nonlinear performance of a quantum dot laser provided in an embodiment of the present disclosure.

[0059] like Figure 4 As shown, the quantum dot laser bandwidth and nonlinear performance coordinating control device 400 of this embodiment includes a construction module 401, an application module 402 and a control module 403.

[0060] Module 401 is used to construct a quantum dot laser as a nonlinear resonator system driven by a bias current.

[0061] The application module 402 is used to apply a bias current to the quantum dot laser.

[0062] The control module 403 is used to set the quantum dot laser to a cooperative bias operating point by controlling the magnitude of the bias current, wherein the cooperative bias operating point is configured to cooperatively increase the relaxation oscillation frequency of the laser and control nonlinear effects.

[0063] It is understood that the construction module 401, the application module 402, and the control module 403 can be implemented in a single module, or any one of these modules can be split into multiple modules. Alternatively, at least some of the functions of one or more of these modules can be combined with at least some of the functions of other modules and implemented in a single module. According to embodiments of this disclosure, at least one of the construction module 401, the application module 402, and the control module 403 can be at least partially implemented as hardware circuitry, such as a field-programmable gate array (FPGA), a programmable logic array (PLA), a system-on-a-chip, a system-on-a-substrate, a system-on-package, an application-specific integrated circuit (ASIC), or can be implemented in hardware or firmware in any other reasonable manner of integrating or packaging circuitry, or in a suitable combination of software, hardware, and firmware implementations. Alternatively, at least one of the construction module 401, the application module 402, and the control module 403 can be at least partially implemented as a computer program module, which, when run by a computer, can execute the functions of the corresponding module.

[0064] Figure 5 The schematic diagram illustrates the hardware structure of an electronic device provided in an embodiment of this disclosure.

[0065] like Figure 5As shown, an electronic device 500 according to an embodiment of the present disclosure includes a processor 501, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 502 or a program loaded from a storage portion 508 into a random access memory (RAM) 503. The processor 501 may include, for example, a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or an associated chipset and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 501 may also include onboard memory for caching purposes. The processor 501 may include a single processing unit or multiple processing units for performing different actions of the method flow according to an embodiment of the present disclosure.

[0066] RAM 503 stores various programs and data required for the operation of electronic device 500. Processor 501, ROM 502, and RAM 503 are interconnected via bus 504. Processor 501 performs various operations of the method flow according to embodiments of the present disclosure by executing programs in ROM 502 and / or RAM 503. It should be noted that programs may also be stored in one or more memories other than ROM 502 and RAM 503. Processor 501 may also perform various operations of the method flow according to embodiments of the present disclosure by executing programs stored in one or more memories.

[0067] According to embodiments of this disclosure, the electronic device 500 may further include an input / output (I / O) interface 505, which is also connected to a bus 504. The electronic device 500 may also include one or more of the following components connected to the input / output (I / O) interface 505: an input section 506 including a keyboard, mouse, etc.; an output section 507 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 508 including a hard disk, etc.; and a communication section 509 including a network interface card such as a LAN card, modem, etc. The communication section 509 performs communication processing via a network such as the Internet. A drive 510 is also connected to the input / output (I / O) interface 505 as needed. A removable medium 511, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on the drive 510 as needed so that computer programs read from it can be installed into the storage section 508 as needed.

[0068] This disclosure also provides a computer-readable medium, which may be included in the device / apparatus / system described in the above embodiments; or it may exist independently and not assembled into the device / apparatus / system. The computer-readable medium carries one or more programs that, when executed, implement the method according to the embodiments of this disclosure.

[0069] Those skilled in the art will understand that the features described in the various embodiments of this disclosure can be combined and / or combined in various ways, even if such combinations and / or combinations are not explicitly described in this disclosure. In particular, the features described in the various embodiments of this disclosure can be combined and / or combined in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or combinations fall within the scope of this disclosure.

[0070] The above specific embodiments further illustrate the purpose, technical solutions and beneficial effects of this disclosure. It should be understood that the above are only specific embodiments of this disclosure and are not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A method for synergistic control of bandwidth and nonlinear performance of a quantum dot laser, characterized in that, The method includes: Constructing a quantum dot laser as a nonlinear resonator system driven by a bias current; A bias current is applied to the quantum dot laser; By adjusting the magnitude of the bias current, the quantum dot laser is set to a cooperative bias operating point, wherein the cooperative bias operating point is configured to cooperatively increase the relaxation oscillation frequency of the laser and control nonlinear effects.

2. The method according to claim 1, characterized in that, The step of setting the quantum dot laser to a cooperative bias operating point by adjusting the magnitude of the bias current includes: The bias current is adjusted to the target bias current value so that the relaxation oscillation frequency of the quantum dot laser is greater than or equal to a preset bandwidth threshold; and The nonlinear distortion generated by the quantum dot laser is limited to a preset application tolerance range, or the quantum dot laser is operated in a preset nonlinear dynamic region.

3. The method according to claim 2, characterized in that, The cooperative bias operating point is the bias current point where the ratio of the relaxation oscillation frequency to the nonlinear distortion of the quantum dot laser reaches a local maximum.

4. The method according to claim 1, characterized in that, Applying a bias current to the quantum dot laser includes: Energy is injected into the nonlinear resonator system by electrically pumping the quantum dot laser with a bias current.

5. The method according to claim 1, characterized in that, The quantum dot laser includes a monolithically integrated quantum dot laser region and a modulation region, and the method further includes: The modulation region receives the continuous optical signal generated by the quantum dot laser region and modulates the continuous optical signal to output an encoded continuous optical signal, wherein the quantum dot laser region is configured to operate at the cooperative bias operating point.

6. The method according to claim 1, characterized in that, The nonlinear resonator system includes an optical resonator cavity, which is composed of a distributed feedback grating.

7. The method according to claim 6, characterized in that, The intrinsic oscillation mode of the nonlinear resonator system is determined by the structure of the distributed feedback grating.

8. A quantum dot laser, characterized in that, The quantum dot laser is configured to be driven by the method described in any one of claims 1 to 7 to operate at a cooperative bias operating point.

9. A device for synergistic control of bandwidth and nonlinear performance of a quantum dot laser, characterized in that, include: Building blocks for constructing quantum dot lasers as nonlinear resonator systems driven by bias current; An application module for applying a bias current to the quantum dot laser; The control module is used to set the quantum dot laser to a cooperative bias operating point by controlling the magnitude of the bias current, wherein the cooperative bias operating point is configured to cooperatively increase the relaxation oscillation frequency of the laser and control nonlinear effects.

10. An electronic device, comprising: One or more processors; Memory, used to store one or more computer programs. The characteristic feature is that the one or more processors execute the one or more computer programs to implement the steps of the method according to any one of claims 1 to 7.

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