Cold atom quantum gate multi-beam narrow linewidth laser synchronous phase locking electric control system

Abstract

The application discloses a kind of cold atom quantum gate multi-beam narrow linewidth laser synchronous phase locking electric control system, it is related to the technical field of laser.The same source clock is generated and unified timing reference is established by global synchronization master module, combined with multi-path synchronous modulation signal output module, cross-laser phase difference real-time extraction module, global unified feedback calibration module and multi-path laser drive frequency locking module, construct the full-digital multi-channel closed-loop phase synchronization control architecture based on unified clock source.The system is through synchronous acquisition each road to be locked laser and the beat frequency detection signal formed by reference laser, real-time solution relative phase shift, and according to phase error generation compensation control quantity, to each road narrow linewidth laser is carried out dynamic phase calibration.The application realizes the integration control of multi-path laser timing synchronization, phase detection and closed-loop compensation, reduces dynamic phase drift, improves the relative phase stability of multi-beam narrow linewidth laser, satisfies the high-precision control demand of cold atom quantum gate.

Description

Technical Field

[0001] This invention relates to the field of laser technology, and more specifically to a phase-locked electronic control system for synchronous multi-beam narrow-linewidth lasers using cold atom quantum gates. Background Technology

[0002] Cold atom quantum computing utilizes the internal energy levels of neutral atoms as qubits, employing multiple narrow-linewidth laser beams to achieve processes such as atomic cooling, trapping, initialization, quantum state manipulation, and state readout. The frequency stability, phase consistency, and timing synchronization accuracy among these multiple laser beams—including the cooling beam, repump beam, probe beam, and quantum gate manipulation beam—directly affect the quantum state evolution process and the fidelity of quantum gate operations.

[0003] In existing cold atom quantum experimental systems, each laser is independently frequency-locked, modulated, and controlled to ensure stable output of a single laser beam. However, the lack of a unified clock synchronization reference among the control modules makes timing deviations easy to occur between different control units. Furthermore, the dynamic phase shift between multiple laser beams is caused by factors such as temperature drift of electronic components, circuit noise, environmental vibration, and optical path disturbances, resulting in reduced relative phase stability between beams.

[0004] To address the aforementioned issues, existing technologies employ optical delay compensation devices or analog compensation circuits to correct phase errors. However, these methods primarily compensate for fixed phase shifts, making it difficult to detect and suppress random phase changes generated during operation. Furthermore, they are susceptible to temperature drift and device inconsistencies, resulting in limited long-term stability. Another approach uses a common frequency reference source to achieve frequency synchronization across multiple laser streams, but this mainly addresses frequency consistency and lacks a digital control mechanism for real-time detection and closed-loop calibration of the relative phase of multiple laser streams.

[0005] Therefore, existing technologies have problems such as the inability to detect and dynamically compensate for phase errors across multiple narrow-linewidth lasers in real time, and insufficient long-term phase synchronization accuracy of multiple beams, making it difficult to meet the requirements for high-precision collaborative control of cold atom quantum gates. Summary of the Invention

[0006] The purpose of this invention is to solve the problem of insufficient phase synchronization accuracy of multi-beam lasers mentioned in the background art, and to propose a cold atom quantum gate multi-beam narrow linewidth laser synchronization phase-locked electronic control system.

[0007] A first aspect of this invention provides a phase-locked electronic control system for synchronous cold atom quantum gate multi-beam narrow-linewidth lasers, the system comprising: The global synchronization master control module is used to generate a global synchronous clock and establish a unified timing reference for all laser control channels in the entire system; A multi-channel synchronous modulation signal output module is used to generate and output multiple time-synchronized laser modulation signals and frequency-locking drive signals in parallel under the control of the unified timing reference. A multi-channel laser driver frequency-locking module is used to receive the laser modulation signal and the frequency-locking drive signal, and drive each narrow linewidth laser accordingly. The real-time phase difference extraction module across lasers is used to receive the beat frequency detection signals formed by each laser to be locked and the reference laser, synchronously sample each beat frequency detection signal, and calculate the real-time relative phase offset of each laser to be locked relative to the reference laser. A global unified feedback calibration module is used to generate independent phase compensation control quantities for each laser based on the relative phase offset, and feed them back to the multi-laser drive frequency locking module. The multi-channel laser drive frequency locking module is also used to receive the phase compensation control quantity and drive each narrow linewidth laser to perform phase fine-tuning accordingly. The global synchronization master control module, the multi-channel synchronous modulation signal output module, the multi-channel laser drive frequency locking module, the cross-laser phase difference real-time extraction module, and the global unified feedback calibration module constitute a fully digital multi-channel closed-loop phase synchronization control architecture based on a unified clock source. Each module performs beat frequency detection, phase calculation, error calculation, and feedback compensation in a cyclical manner under unified timing control to maintain the target phase relationship of each laser.

[0008] Optionally, the global synchronization master control module includes: The reference clock input interface is used to connect to the reference clock signal provided by an external temperature-controlled crystal oscillator; The clock division and multiplication logic unit is used to perform frequency multiplication and division processing on the reference clock signal to generate a globally homogeneous clock. The synchronous scheduling logic unit is used to generate multiple unified timing control signals that are of the same source, frequency, and phase according to the global synchronous clock, and output them to the multi-channel synchronous modulation signal output module, the real-time extraction module of phase difference across lasers, and the global unified feedback calibration module, respectively, so as to uniformly schedule the timing of each module in the whole system.

[0009] Optionally, the multi-channel synchronous modulation signal output module includes: A multi-channel digital frequency synthesis logic unit generates multiple time-synchronized laser modulated digital signals based on the unified timing control signal. The frequency, phase, and amplitude of each signal can be independently and programmably configured. A multi-channel digital-to-analog converter output interface is connected to the digital frequency synthesis logic unit and is used to synchronously convert the laser modulation digital signal into an analog voltage signal and output it to the multi-channel laser drive frequency locking module. The digital-to-analog conversion update trigger signals of all channels are derived from the unified timing control signal.

[0010] Optionally, the real-time phase difference extraction module across lasers includes: A multi-channel beat frequency detection interface is used to optically couple each of the lasers to be locked with a reference laser to form a beat frequency signal; The photoelectric detection unit is used to detect beat frequency signals and convert them into electrical signals; A multi-channel synchronous analog-to-digital converter control interface is used to synchronously acquire the beat frequency electrical signals of each laser. The sampling trigger clock of all channels comes from the same timing control signal provided by the global synchronization main control module. The phase calculation logic unit is used to calculate the relative phase offset between any laser and the reference laser in real time based on the digital phase detection algorithm.

[0011] Optionally, the global unified feedback calibration module has a built-in digital PID control logic unit; The digital PID control logic unit independently configures a set of fixed-stored PID parameters and a preset target phase offset value for each laser channel. The digital PID control logic unit uses the difference between the measured relative phase offset of each laser channel relative to the reference laser and its corresponding target phase offset value as the error input signal, and generates independent phase compensation control quantities for each channel according to the control law of proportional, integral and derivative weighted synthesis. The phase compensation control quantities include piezoelectric ceramic compensation control quantities and laser injection current compensation control quantities.

[0012] Optionally, the multi-channel laser drive frequency locking module includes multiple laser drive units that are configured one-to-one with the laser channels, and each laser drive unit receives the frequency locking drive signal and phase compensation control amount of the corresponding channel. Each laser driving unit includes: A frequency locking control unit is used to drive a corresponding narrow-linewidth laser to complete frequency locking according to the frequency locking drive signal; A piezoelectric ceramic driving unit, connected to the frequency locking control unit, is used to adjust the cavity length of the laser resonant cavity according to the phase compensation control amount to compensate for low-frequency phase drift. A laser current modulation unit, connected to the frequency locking control unit, is used to adjust the laser injection current according to the phase compensation control amount to compensate for high-frequency phase disturbances.

[0013] Optionally, the PID parameters of each laser channel are constants that are fixed and stored in the system parameter storage area after offline tuning by the optimization algorithm. During the offline tuning stage, the optimization algorithm uses the minimum weighted sum of multiple performance indicators as the optimization objective for parameter optimization. The multiple performance indicators include: the sum of the time integrals of the absolute values ​​of the phase errors of each laser channel within a preset time window, and the sum of the variances of the phase errors of each laser channel within the time window. The constraints are that the integral of the absolute value of the change rate of the phase compensation control quantity of each laser channel is less than the corresponding first preset threshold and the integral of the absolute value of the change rate of the phase error of each laser channel is less than the corresponding second preset threshold. The phase error is the deviation between the measured relative phase offset of each laser channel and its preset target phase offset. The constraints are added to the optimization objective in the form of a penalty function during the optimization process. When any constraint is not satisfied, a penalty is imposed on the current candidate solution, causing its fitness to deteriorate and it to be excluded from the optimal solution.

[0014] Optionally, the system further includes a parameter tuning module for optimizing the PID parameters of each laser channel, using a hybrid swarm intelligence optimization algorithm based on a competitive update mechanism; the parameter tuning module includes: The population initialization module is used to initialize multiple individuals, and the position vector of each individual is randomly initialized within a preset range. The candidate solution competition module generates two candidate solutions in parallel for each individual in the current population: a particle swarm optimization candidate solution and a manta ray foraging optimization candidate solution. It calculates the fitness values ​​of the two candidate solutions and uses a greedy selection mechanism to choose the candidate solution with the best fitness as the new position for that individual. The particle swarm optimization candidate solution is generated based on the velocity and position update equations of the particle swarm optimization algorithm, while the manta ray foraging optimization candidate solution is generated based on the manta ray's chain foraging strategy or vortex foraging strategy. The manta ray foraging optimization module is used to update the individual's position around the current global best position for each individual after competitive selection, based on the manta ray's backflip foraging strategy. If the fitness of the updated individual is better than that of the previous individual, the update is accepted. The mutation module is used to perform Gaussian mutation on the current individual to generate new candidate solutions. If the fitness of the mutated individual is better than that of the original individual, the mutation is accepted. The global optimal update module is used to update the historical optimal position of all individuals and traverse the entire population to determine the global optimal position. The termination control module terminates the iteration if the maximum number of iterations is reached, and outputs the PID parameter combination corresponding to the globally optimal position as the optimal PID parameter combination; otherwise, it returns to the candidate solution competition module to continue iteration.

[0015] Optionally, the fitness calculation formula is as follows: ; Where F is the desired fitness; M is the total number of participating laser channels; and T is the preset time window. It is the phase error of the i-th channel; It is the variance of the phase error of the i-th channel within T; penalty is the penalty term; It is the rate of change of the phase compensation control quantity of the i-th channel; It is the rate of change of the phase error of the i-th channel; , These are the first preset threshold and the second preset threshold corresponding to the i-th channel, respectively. It is a positive part function; , , It is the weighting coefficient.

[0016] The beneficial effects of this invention are: 1. This invention generates a co-current clock and establishes a unified timing reference for the entire system through a global synchronization master control module. Combined with a multi-channel synchronous modulation signal output module, a real-time phase difference extraction module across lasers, and a globally unified feedback calibration module, it constructs a fully digital multi-channel closed-loop phase synchronization control architecture. Compared to the existing technology of independent frequency locking and modulation for multiple lasers, this invention eliminates timing deviations between control modules at the source. This ensures that beat frequency detection, phase calculation, error calculation, and feedback compensation are all performed cyclically under a unified timing cycle, significantly improving the relative phase stability between multiple narrow-linewidth lasers. It effectively suppresses dynamic phase drift caused by electronic device temperature drift, circuit noise, and environmental vibration, meeting the stringent requirements of cold atom quantum gate operations for high-precision coordinated control of multiple beams.

[0017] 2. This invention independently configures PID parameters in each laser channel and suppresses low-frequency drift and high-frequency disturbances through dual-path compensation of piezoelectric ceramics and injection current, thereby improving the bandwidth and accuracy of phase locking. Simultaneously, it employs fixed PID parameters tuned offline using an optimized algorithm, combined with a hybrid swarm intelligent optimization algorithm based on a competitive update mechanism for parameter optimization. This allows for the rapid acquisition of globally optimal control parameters for complex systems with multiple channels and constraints, ensuring high robustness and consistency of the system during long-term operation. Attached Figure Description

[0018] Figure 1 An architecture diagram of a cold atom quantum gate multi-beam narrow linewidth laser synchronization phase-locked electronic control system provided in an embodiment of the present invention; Figure 2 A flowchart illustrating the operation of a cold atom quantum gate multi-beam narrow-linewidth laser synchronous phase-locked electronic control system provided in this embodiment of the invention. Detailed Implementation

[0019] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of the present invention is provided in conjunction with the accompanying drawings and preferred embodiments.

[0020] This invention provides an electronically controlled system for synchronous phase-locking of cold atom quantum gate multi-beam narrow-linewidth lasers. See also... Figure 1 The system includes: The global synchronization master control module is used to generate a global synchronous clock and establish a unified timing reference for all laser control channels in the entire system.

[0021] The multi-channel synchronous modulation signal output module is used to generate and output multiple time-synchronized laser modulation signals and frequency-locked drive signals in parallel under the control of a unified timing reference.

[0022] The multi-channel laser driver frequency-locking module is used to receive laser modulation signals and frequency-locking drive signals, and drive each narrow-linewidth laser accordingly.

[0023] The real-time phase difference extraction module across lasers is used to receive the beat frequency detection signals formed by each laser to be locked and the reference laser, synchronously sample each beat frequency detection signal, and calculate the real-time relative phase offset of each laser to be locked relative to the reference laser.

[0024] The global unified feedback calibration module is used to generate independent phase compensation control quantities for each laser based on the relative phase offset, and feed them back to the multi-laser drive frequency locking module.

[0025] The multi-channel laser driver frequency locking module is also used to receive phase compensation control signals and drive each narrow-linewidth laser to perform phase fine-tuning accordingly.

[0026] Among them, the global synchronization master control module, the multi-channel synchronous modulation signal output module, the multi-channel laser drive frequency locking module, the cross-laser phase difference real-time extraction module, and the global unified feedback calibration module constitute a fully digital multi-channel closed-loop phase synchronization control architecture based on a unified clock source. Each module performs beat frequency detection, phase calculation, error calculation, and feedback compensation in a cyclical manner under unified timing control in order to maintain the target phase relationship of each laser.

[0027] In one embodiment, the global synchronization master control module includes: The reference clock input interface is used to connect to the reference clock signal provided by an external temperature-controlled crystal oscillator.

[0028] The clock divider and multiplier logic unit is used to multiply and divide the reference clock signal to generate a globally homogeneous clock.

[0029] The synchronous scheduling logic unit is used to generate multiple unified timing control signals that are of the same source, frequency, and phase according to the global clock, and output them to the multi-channel synchronous modulation signal output module, the real-time extraction module of phase difference across lasers, and the global unified feedback calibration module, respectively, so as to uniformly schedule the timing of each module in the whole system.

[0030] This embodiment utilizes an externally sourced, temperature-controlled crystal oscillator to provide a high-stability reference clock. A global, homogeneous clock is then generated via clock division and multiplication logic units. A synchronous scheduling logic unit generates multiple unified timing control signals that are homogeneous, synchronous, and synchronous in phase. This provides a low-jitter, highly consistent timing reference for all modules in the system, fundamentally avoiding the cumulative timing deviations introduced by each module using an independent clock source. It ensures that critical actions such as beat sampling, digital-to-analog conversion, and feedback updates are strictly aligned in time, laying a reliable clock foundation for high-precision phase locking.

[0031] In one implementation, the global synchronization main control module is implemented based on an FPGA (Field-Programmable Gate Array). Provided that multi-channel synchronous timing output and high-speed parallel computing capabilities are met, it can be replaced with digital main control chips such as CPLDs (Complex Programmable Logic Devices), high-performance DSPs (Digital Signal Processors), and industrial-grade high-speed microcontrollers. As long as global synchronization control with a common clock source and integrated electronic control logic are achieved, these are all conventional replacements within the scope of this invention.

[0032] In one embodiment, the multi-channel synchronous modulation signal output module includes: The multi-channel digital frequency synthesis logic unit generates multiple time-synchronized laser modulated digital signals based on a unified timing control signal. The frequency, phase, and amplitude of each signal can be independently and programmably configured.

[0033] The multi-channel digital-to-analog converter output interface is connected to the digital frequency synthesis logic unit to synchronously convert the laser modulation digital signal into an analog voltage signal and output it to the multi-channel laser drive frequency locking module. The digital-to-analog conversion update trigger signals of all channels are derived from the unified timing control signal.

[0034] This embodiment generates independent programmable modulated digital signals based on a unified timing control signal through a multi-channel digital frequency synthesis logic unit, and achieves synchronous analog output by using a digital-to-analog conversion update trigger signal shared by all channels. This ensures that the laser modulation signals are strictly synchronized in timing, while allowing the frequency, phase and amplitude of each signal to be flexibly configured according to actual needs. This adapts to the different modulation parameter requirements of different lasers (such as cooling light, repump light, probe light, etc.) in cold atom experiments, while avoiding the additional phase noise introduced by asynchronous updates.

[0035] In one embodiment, the real-time phase difference extraction module across lasers includes: The multi-channel beat frequency detection interface is used to optically couple each of the lasers to be locked with the reference laser to form a beat frequency signal.

[0036] The photoelectric detection unit is used to detect beat frequency signals and convert them into electrical signals.

[0037] The multi-channel synchronous analog-to-digital converter control interface is used to synchronously acquire the beat frequency electrical signals of each laser. The sampling trigger clock of all channels comes from the same timing control signal provided by the global synchronous main control module.

[0038] The phase calculation logic unit is used to calculate the relative phase offset between any laser and the reference laser in real time based on the digital phase detection algorithm.

[0039] In one implementation, the reference laser originates from a designated narrow-linewidth laser within the system. This laser shares the same global timing reference with other lasers to be locked and, after frequency locking, serves as the phase reference source for the entire system. Alternatively, a separate reference laser with an even narrower linewidth and higher frequency stability can be added, dedicated to providing a beat frequency reference source.

[0040] In one implementation, the digital phase detection algorithm employs a digital I / Q (in-phase / quadrature) demodulation algorithm, an FFT (Fast Fourier Transform) phase detection algorithm, and an adaptive filtering phase extraction algorithm.

[0041] This embodiment utilizes a multi-channel beat frequency detection interface and a photoelectric detection unit to convert optical beat frequency signals into electrical signals. A global synchronization main control module provides a unified timing control signal to trigger multi-channel synchronous analog-to-digital conversion, ensuring that the beat frequency signals of all channels are sampled at the same time, eliminating phase measurement errors caused by inconsistent sampling times. The phase calculation logic unit calculates the relative phase offset in real time based on a digital phase detection algorithm, providing accurate and low-latency error input for subsequent feedback calibration. This enables the system to respond promptly to phase changes and improves the closed-loop control bandwidth.

[0042] In one embodiment, the global unified feedback calibration module incorporates a digital PID control logic unit. This unit independently configures a set of permanently stored PID parameters and a preset target phase offset value for each laser channel. The digital PID control logic unit uses the difference between the measured relative phase offset of each laser channel relative to the reference laser and its corresponding target phase offset value as the error input signal, and generates independent phase compensation control quantities for each channel according to a weighted control law of proportional, integral, and derivative terms. These phase compensation control quantities include piezoelectric ceramic compensation control quantities and laser injection current compensation control quantities.

[0043] In one embodiment, the PID parameters of each laser channel are constants that are fixed and stored in the system parameter storage area after being tuned offline by an optimization algorithm.

[0044] The optimization algorithm uses the minimum weighted sum of multiple performance indicators as the optimization objective during the offline tuning phase. These performance indicators include: the sum of the absolute values ​​of the phase errors of each laser channel over time within a preset time window, and the sum of the variances of the phase errors of each laser channel within the time window.

[0045] Furthermore, the constraints are that the integral of the absolute value of the change rate of the phase compensation control quantity of each laser channel is less than the corresponding first preset threshold, and the integral of the absolute value of the change rate of the phase error of each laser channel is less than the corresponding second preset threshold. Here, the phase error is the deviation between the measured relative phase offset of each laser channel and its preset target phase offset.

[0046] Constraints are added to the optimization objective in the form of a penalty function during the optimization process. When any constraint is not satisfied, a penalty is imposed on the current candidate solution, causing its fitness to deteriorate and it to be excluded from the optimal solution.

[0047] The optimization objective of this embodiment simultaneously considers the cumulative amount and volatility of phase error, and uses integral limits of the control variable change rate and error change rate as constraints to effectively prevent system oscillations caused by overcompensation or drastic changes in the control variable. By incorporating the constraints into the optimization objective through a penalty function, the optimization process automatically eliminates candidate solutions that do not meet the stability requirements. The final PID parameters ensure both rapid convergence of phase error and stable system operation, significantly enhancing the engineering reliability of the multi-channel closed-loop system.

[0048] In one embodiment, the system further includes a parameter tuning module for optimizing the PID parameters of each laser channel, using a hybrid swarm intelligence optimization algorithm based on a competitive update mechanism. The parameter tuning module includes: The population initialization module is used to initialize multiple individuals, and the position vector of each individual is randomly initialized within a preset range. The candidate solution competition module generates two candidate solutions in parallel for each individual in the current population: a particle swarm optimization candidate solution and a manta ray foraging optimization candidate solution. It calculates the fitness values ​​of the two candidate solutions and uses a greedy selection mechanism to choose the candidate solution with the best fitness as the individual's new position. The particle swarm optimization candidate solution is generated based on the velocity and position update equations of the particle swarm optimization algorithm, while the manta ray foraging optimization candidate solution is generated based on the manta ray's chain foraging strategy or vortex foraging strategy. The manta ray foraging optimization module is used to update the individual's position around the current global best position for each individual after competitive selection, based on the manta ray's backflip foraging strategy. If the fitness of the updated individual is better than that of the previous individual, the update is accepted. The mutation module is used to perform Gaussian mutation on the current individual to generate new candidate solutions. If the fitness of the mutated individual is better than that of the original individual, the mutation is accepted. The global optimal update module is used to update the historical optimal position of all individuals and traverse the entire population to determine the global optimal position. The termination control module terminates the iteration if the maximum number of iterations is reached, and outputs the PID parameter combination corresponding to the globally optimal position as the optimal PID parameter combination; otherwise, it returns to the candidate solution competition module to continue iteration.

[0049] In one implementation, the formula for calculating fitness is: ; Where F is the desired fitness; M is the total number of participating laser channels; and T is the preset time window. It is the phase error of the i-th channel; It is the variance of the phase error of the i-th channel within T; penalty is the penalty term; It is the rate of change of the phase compensation control quantity of the i-th channel; It is the rate of change of the phase error of the i-th channel; , These are the first preset threshold and the second preset threshold corresponding to the i-th channel, respectively. It is a positive part function. ; , , These are weighting coefficients. Much larger and ,For example, , , It can take the values ​​1, 1, and 100 respectively.

[0050] In one implementation, the first preset threshold This is the upper limit of the integral of the absolute value of the rate of change of the phase compensation control quantity of the i-th channel. Its value depends on the response capability and output saturation characteristics of the piezoelectric ceramic driving unit and the laser current modulation unit in the corresponding laser channel. Specifically, by applying a step control signal to each laser driving unit and measuring its output response curve, the maximum allowable rate of change of the control quantity for that channel is obtained. After multiplying this maximum allowable rate of change by a preset safety factor (within the range of 0.5-0.8), the result is integrated within a preset time window T to obtain the first preset threshold for that channel. This threshold is used to constrain the rate of change of the phase compensation control quantity, preventing the feedback compensation quantity from changing too quickly, which could lead to saturation of the piezoelectric ceramic driving unit or overshoot of the laser current modulation unit, thereby ensuring the stability of the system.

[0051] In one implementation, the second preset threshold This is the upper limit of the integral of the absolute value of the phase error change rate of the i-th channel. Its value depends on the specific requirements of cold atom quantum gate manipulation for phase stability and the closed-loop bandwidth of the system. Specifically, the maximum allowable phase error change rate is calculated by back-calculating the quantum gate operation fidelity index. This maximum phase error change rate is then multiplied by a preset margin coefficient (ranging from 1.2 to 2.0) and integrated within a preset time window T to obtain the second preset threshold for that channel. This threshold is used to constrain the rate of change of the phase error, ensuring that the phase error can converge smoothly during the closed-loop feedback process, avoiding system oscillations caused by excessively rapid error changes, and ensuring that phase fluctuations during quantum gate manipulation are within an acceptable range.

[0052] This embodiment employs a hybrid swarm optimization algorithm based on a competitive update mechanism. This algorithm combines the fast convergence capability of particle swarm optimization with the multi-strategy exploration capability of manta ray foraging optimization. By generating two candidate solutions in parallel and greedily selecting the optimal one, it effectively balances global search and local exploitation, avoiding the pitfalls of traditional single algorithms that are prone to getting trapped in local optima. The introduction of the backflip foraging strategy and Gaussian mutation operation further increases population diversity, improving the algorithm's optimization accuracy and convergence speed in high-dimensional, multi-modal parameter spaces.

[0053] In one embodiment, the multi-channel laser drive frequency locking module includes multiple laser drive units that are configured one-to-one with the laser channels. Each laser drive unit receives the frequency locking drive signal and phase compensation control amount of the corresponding channel.

[0054] Each laser driving unit includes: The frequency locking control unit is used to drive the corresponding narrow-linewidth laser to complete frequency locking according to the frequency locking drive signal.

[0055] The piezoelectric ceramic drive unit, connected to the frequency-locked control unit, is used to adjust the cavity length of the laser resonant cavity according to the phase compensation control amount to compensate for low-frequency phase drift.

[0056] The laser current modulation unit, connected to the frequency locking control unit, is used to adjust the laser injection current according to the phase compensation control quantity to compensate for high-frequency phase disturbances.

[0057] This embodiment combines the frequency locking control unit with the piezoelectric ceramic driving unit and the laser current modulation unit to achieve integrated driving of laser frequency locking and phase fine-tuning. The piezoelectric ceramic driving unit performs large-stroke compensation for low-frequency phase drift caused by temperature drift and mechanical vibration, while the laser current modulation unit provides rapid response to high-frequency phase disturbances caused by power supply noise and rapid disturbances. Their collaborative operation expands the frequency band of phase compensation and improves the system's ability to suppress disturbances of different frequencies, thereby effectively enhancing the stability of long-term phase maintenance of multiple laser beams.

[0058] In one embodiment, see Figure 2 The overall system workflow is as follows: S1. System Initialization: The global synchronization main control module completes the global same-source clock configuration, establishes a unified system timing reference, and completes the initial parameter configuration, phase reference calibration, and hardware self-test of multiple laser channels.

[0059] S2. Initial frequency lock: The multi-channel synchronous modulation signal output module is based on the same source and unified clock, and outputs multiple time-synchronized and parameter-independent laser modulation and frequency lock drive signals in parallel to drive each narrow linewidth laser to work stably and complete the initial frequency lock.

[0060] S3. Detecting relative phase shift: The real-time phase difference extraction module across lasers synchronously acquires the real-time phase signals of each laser beam and solves the relative phase shift and dynamic jitter data between beams in real time through the built-in calculation algorithm.

[0061] S4. Phase Compensation Calculation and Dynamic Correction: The global unified feedback calibration module compares the real-time phase offset data with the system's preset target phase offset, and generates a dedicated phase compensation amount for each channel through global overall calculation, dynamically correcting the operating parameters of each laser.

[0062] S5. Closed-loop control: The system continuously cycles through phase acquisition, deviation calculation and feedback calibration processes to form a fully digital closed-loop phase synchronization locking mechanism, continuously suppressing multi-beam phase jitter and drift, and maintaining long-term high-precision phase synchronization of multiple lasers.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention are within the scope of the claims of the present invention.

Claims

1. A phase-locked electronic control system for synchronous cold atom quantum gate multi-beam narrow-linewidth lasers, characterized in that, The system includes: The global synchronization master control module is used to generate a global synchronous clock and establish a unified timing reference for all laser control channels in the entire system; A multi-channel synchronous modulation signal output module is used to generate and output multiple time-synchronized laser modulation signals and frequency-locking drive signals in parallel under the control of the unified timing reference. A multi-channel laser driver frequency-locking module is used to receive the laser modulation signal and the frequency-locking drive signal, and drive each narrow linewidth laser accordingly. The real-time phase difference extraction module across lasers is used to receive the beat frequency detection signals formed by each laser to be locked and the reference laser, synchronously sample each beat frequency detection signal, and calculate the real-time relative phase offset of each laser to be locked relative to the reference laser. A global unified feedback calibration module is used to generate independent phase compensation control quantities for each laser based on the relative phase offset, and feed them back to the multi-laser drive frequency locking module. The multi-channel laser drive frequency locking module is also used to receive the phase compensation control quantity and drive each narrow linewidth laser to perform phase fine-tuning accordingly. The global synchronization master control module, the multi-channel synchronous modulation signal output module, the multi-channel laser drive frequency locking module, the cross-laser phase difference real-time extraction module, and the global unified feedback calibration module constitute a fully digital multi-channel closed-loop phase synchronization control architecture based on a unified clock source. Each module performs beat frequency detection, phase calculation, error calculation, and feedback compensation in a cyclical manner under unified timing control to maintain the target phase relationship of each laser.

2. The cold atom quantum gate multi-beam narrow linewidth laser synchronous phase-locked electronic control system according to claim 1, characterized in that, The global synchronization master control module includes: The reference clock input interface is used to connect to the reference clock signal provided by an external temperature-controlled crystal oscillator; The clock division and multiplication logic unit is used to perform frequency multiplication and division processing on the reference clock signal to generate a globally homogeneous clock. The synchronous scheduling logic unit is used to generate multiple unified timing control signals that are of the same source, frequency, and phase according to the global synchronous clock, and output them to the multi-channel synchronous modulation signal output module, the real-time extraction module of phase difference across lasers, and the global unified feedback calibration module, respectively, so as to uniformly schedule the timing of each module in the whole system.

3. The cold atom quantum gate multi-beam narrow linewidth laser synchronous phase-locked electronic control system according to claim 2, characterized in that, The multi-channel synchronous modulation signal output module includes: A multi-channel digital frequency synthesis logic unit generates multiple time-synchronized laser modulated digital signals based on the unified timing control signal. The frequency, phase, and amplitude of each signal can be independently and programmably configured. A multi-channel digital-to-analog converter output interface is connected to the digital frequency synthesis logic unit and is used to synchronously convert the laser modulation digital signal into an analog voltage signal and output it to the multi-channel laser drive frequency locking module. The digital-to-analog conversion update trigger signals of all channels are derived from the unified timing control signal.

4. The cold atom quantum gate multi-beam narrow linewidth laser synchronous phase-locked electronic control system according to claim 3, characterized in that, The real-time phase difference extraction module across lasers includes: A multi-channel beat frequency detection interface is used to optically couple each of the lasers to be locked with a reference laser to form a beat frequency signal; The photoelectric detection unit is used to detect beat frequency signals and convert them into electrical signals; A multi-channel synchronous analog-to-digital converter control interface is used to synchronously acquire the beat frequency electrical signals of each laser. The sampling trigger clock of all channels comes from the same timing control signal provided by the global synchronization main control module. The phase calculation logic unit is used to calculate the relative phase offset between any laser and the reference laser in real time based on the digital phase detection algorithm.

5. The cold atom quantum gate multi-beam narrow linewidth laser synchronous phase-locked electronic control system according to claim 4, characterized in that, The global unified feedback calibration module has a built-in digital PID control logic unit. The digital PID control logic unit independently configures a set of fixed-stored PID parameters and a preset target phase offset value for each laser channel. The digital PID control logic unit uses the difference between the measured relative phase offset of each laser channel relative to the reference laser and its corresponding target phase offset value as the error input signal, and generates independent phase compensation control quantities for each channel according to the control law of proportional, integral and derivative weighted synthesis. The phase compensation control quantities include piezoelectric ceramic compensation control quantities and laser injection current compensation control quantities.

6. The cold atom quantum gate multi-beam narrow linewidth laser synchronous phase-locked electronic control system according to claim 5, characterized in that, The multi-channel laser drive frequency locking module includes multiple laser drive units that are configured one-to-one with the laser channels. Each laser drive unit receives the frequency locking drive signal and phase compensation control amount of the corresponding channel. Each laser driving unit includes: A frequency locking control unit is used to drive a corresponding narrow-linewidth laser to complete frequency locking according to the frequency locking drive signal; A piezoelectric ceramic driving unit, connected to the frequency locking control unit, is used to adjust the cavity length of the laser resonant cavity according to the phase compensation control amount to compensate for low-frequency phase drift. A laser current modulation unit, connected to the frequency locking control unit, is used to adjust the laser injection current according to the phase compensation control amount to compensate for high-frequency phase disturbances.

7. The cold atom quantum gate multi-beam narrow linewidth laser synchronous phase-locked electronic control system according to claim 6, characterized in that, The PID parameters of each laser channel are constants that are fixed and stored in the system parameter storage area after being tuned offline by an optimization algorithm. The optimization algorithm uses the minimum weighted sum of multiple performance indicators as the optimization objective during the offline tuning phase. These multiple performance indicators include: the sum of the time integrals of the absolute values ​​of the phase errors of each laser channel within a preset time window, and the sum of the variances of the phase errors of each laser channel within the time window. Constraints are set as follows: the integral of the absolute value of the change rate of the phase compensation control quantity of each laser channel is less than the corresponding first preset threshold, and the integral of the absolute value of the change rate of the phase error of each laser channel is less than the corresponding second preset threshold. The phase error is the deviation between the measured relative phase offset of each laser channel and its preset target phase offset. These constraints are added to the optimization objective in the form of a penalty function during the optimization process. When any constraint is not met, a penalty is applied to the current candidate solution, causing its fitness to deteriorate and it to be excluded from the optimal solution.

8. The cold atom quantum gate multi-beam narrow linewidth laser synchronous phase-locked electronic control system according to claim 7, characterized in that, The system also includes a parameter tuning module for optimizing the PID parameters of each laser channel. The optimization algorithm used is a hybrid swarm intelligence optimization algorithm based on a competitive update mechanism. The parameter tuning module includes: The population initialization module is used to initialize multiple individuals, and the position vector of each individual is randomly initialized within a preset range. The candidate solution competition module generates two candidate solutions in parallel for each individual in the current population: a particle swarm optimization candidate solution and a manta ray foraging optimization candidate solution. It calculates the fitness values ​​of the two candidate solutions and uses a greedy selection mechanism to choose the candidate solution with the best fitness as the new position for that individual. The particle swarm optimization candidate solution is generated based on the velocity and position update equations of the particle swarm optimization algorithm, while the manta ray foraging optimization candidate solution is generated based on the manta ray's chain foraging strategy or vortex foraging strategy. The manta ray foraging optimization module is used to update the individual's position around the current global best position for each individual after competitive selection, based on the manta ray's backflip foraging strategy. If the fitness of the updated individual is better than that of the previous individual, the update is accepted. The mutation module is used to perform Gaussian mutation on the current individual to generate new candidate solutions. If the fitness of the mutated individual is better than that of the original individual, the mutation is accepted. The global optimal update module is used to update the historical optimal position of all individuals and traverse the entire population to determine the global optimal position. The termination control module terminates the iteration if the maximum number of iterations is reached, and outputs the PID parameter combination corresponding to the globally optimal position as the optimal PID parameter combination; otherwise, it returns to the candidate solution competition module to continue iteration.

9. The cold atom quantum gate multi-beam narrow linewidth laser synchronous phase-locked electronic control system according to claim 8, characterized in that, The formula for calculating fitness is: ； Where F is the desired fitness; M is the total number of participating laser channels; and T is the preset time window. It is the phase error of the i-th channel; It is the variance of the phase error of the i-th channel within T; penalty is the penalty term; It is the rate of change of the phase compensation control quantity of the i-th channel; It is the rate of change of the phase error of the i-th channel; , These are the first preset threshold and the second preset threshold corresponding to the i-th channel, respectively. It is a positive part function; , , It is the weighting coefficient.

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