True random number generation method and system based on optical frequency comb

Abstract

The present disclosure provides a method and system for generating true random numbers based on an optical frequency comb, which relates to the field of laser technology, wherein the method includes: using a fiber laser to generate an optical frequency comb with a preset repetition frequency; using a wavelength division device to divide the laser signal output by the optical frequency comb into multiple laser component signals with different frequencies; using multiple interferometer modules to perform phase transformation and coupling processing on the multiple laser component signals respectively, to obtain multiple laser signals with random light intensities; using a photoelectric detector to convert the multiple laser signals with random light intensities into multiple random analog electrical signals; using a data processing module to generate true random numbers based on the multiple random analog electrical signals and output them. The method and system disclosed in the present disclosure can improve the true random number generation rate based on the stability of the optical frequency comb spectrum and the large spectrum range, and can reduce the selection cost of the wavelength division device.

Description

Technical Field

[0001] The present disclosure relates to the field of laser technology, and in particular to a method and system for generating true random numbers based on an optical frequency comb. Background Art

[0002] Random numbers are a set of unpredictable data. They are widely used in ensuring information security and fairness (such as quantum key distribution BB84 protocol). Random numbers are divided into true random numbers and pseudo-random numbers. Pseudo-random numbers refer to data sequences that are generated based on the computational complexity of the algorithm. Once the initial value is determined, the random number is also determined. Therefore, the randomness of pseudo-random numbers is not truly random, and in theory it can be cracked. The generation of true random numbers depends on random physical processes, and the random numbers generated in this way are unpredictable. These random physical processes include thermal noise, phase of light, and polarization state, etc. Therefore, true random numbers are more secure than pseudo-random numbers. At present, the rate at which traditional true random number generators generate random numbers is low and the cost is high. Summary of the invention

[0003] In view of this, a technical problem to be solved by the present invention is to provide a method and system for generating true random numbers based on an optical frequency comb.

[0004] According to a first aspect of the present disclosure, a method for generating true random numbers based on an optical frequency comb is provided, comprising: using an optical fiber laser to generate an optical frequency comb with a preset repetition frequency; dividing a laser signal output by the optical frequency comb into a plurality of laser component signals with different frequencies by a wavelength division device; performing phase transformation and coupling processing on the plurality of laser component signals respectively by a plurality of interferometer modules to obtain a plurality of laser signals with random light intensities; converting the plurality of laser signals with random light intensities into a plurality of random analog electrical signals by a photodetector; and generating and outputting true random numbers based on the plurality of random analog electrical signals by a data processing module.

[0005] Optionally, the use of a fiber laser to generate an optical frequency comb with a preset repetition frequency includes: using the fiber laser as a laser light source; obtaining the optical frequency comb by controlling the repetition frequency and carrier envelope frequency shift of a femtosecond laser generated by the laser light source; wherein the optical frequency comb outputs a femtosecond pulse laser with the repetition frequency in the time domain.

[0006] Optionally, the fiber laser comprises: a dispersion managed mode-locked fiber laser.

[0007] Optionally, dividing the laser signal output by the optical frequency comb into a plurality of laser component signals with different frequencies by means of a wavelength division device comprises: dividing the femtosecond pulse laser output by the optical frequency comb into a plurality of first single longitudinal mode laser beams with different wavelengths by means of the wavelength division device.

[0008] Optionally, the wavelength division device for performing wavelength division processing on the femtosecond pulse laser output by the optical frequency comb is selected based on the distance between adjacent frequency spectra of the optical frequency comb and the spectrum width.

[0009] Optionally, the interferometer module includes: a first coupler, an interferometer unit and a second coupler; the phase transformation and coupling processing of the multiple laser component signals are respectively performed through multiple interferometer modules to obtain multiple laser signals with random light intensities, including: inputting the first single longitudinal mode laser into the first coupler to obtain two beams of second single longitudinal mode lasers output by the first coupler; inputting the two beams of second single longitudinal mode lasers into the interferometer unit, the interferometer unit is used to change the phase of one beam of second single longitudinal mode laser, and not process the other beam of second single longitudinal mode laser; coupling the two beams of second single longitudinal mode lasers through the second coupler to obtain a beam of laser signal with random light intensity.

[0010] Optionally, the data processing module includes: an analog-to-digital conversion device; generating and outputting true random numbers based on the multiple random analog electrical signals through the data processing module includes: converting the multiple random analog electrical signals into the multiple random digital electrical signals through the analog-to-digital conversion device, generating and outputting true random numbers based on the multiple random digital electrical signals.

[0011] According to a second aspect of the present disclosure, a true random number generation system based on an optical frequency comb is provided, comprising: a fiber laser for generating an optical frequency comb with a preset repetition frequency; a wavelength division device for dividing a laser signal output by the optical frequency comb into a plurality of laser component signals with different frequencies; a plurality of interferometer modules for performing phase transformation and coupling processing on the plurality of laser component signals, respectively, to obtain a plurality of laser signals with random light intensities; a photodetector for converting the plurality of laser signals with random light intensities into a plurality of random analog electrical signals; and a data processing module for generating and outputting true random numbers based on the plurality of random analog electrical signals.

[0012] Optionally, the fiber laser is used as a laser light source, and the optical frequency comb is obtained by controlling the repetition frequency and carrier envelope frequency shift of the femtosecond laser generated by the laser light source; wherein the optical frequency comb outputs femtosecond pulse laser of the repetition frequency in the time domain.

[0013] Optionally, the fiber laser comprises: a dispersion managed mode-locked fiber laser.

[0014] Optionally, the wavelength division device is used to divide the femtosecond pulse laser output by the optical frequency comb into multiple beams of first single longitudinal mode lasers with different wavelengths.

[0015] Optionally, the interferometer module includes: a first coupler, an interferometer unit and a second coupler; the first coupler is used to divide the input first single longitudinal mode laser into two beams of second single longitudinal mode laser; the interferometer unit is used to receive the two beams of second single longitudinal mode laser, change the phase of one beam of second single longitudinal mode laser, and do not process the other beam of second single longitudinal mode laser; the second coupler is used to couple the two beams of second single longitudinal mode laser to obtain a laser signal with random light intensity.

[0016] Optionally, the data processing module includes: an analog-to-digital conversion device; the analog-to-digital conversion device is used to convert the multiple random analog electrical signals into the multiple random digital electrical signals, generate true random numbers based on the multiple random digital electrical signals, and output them.

[0017] The disclosed method and system for generating true random numbers based on an optical frequency comb obtains a plurality of random optical signals by inputting the frequency components of the optical frequency comb into an interferometer, converts the random optical signals into random electrical signals through a photodetector, and converts the random analog electrical signals into random digital electrical signals through an analog-to-digital conversion device. The method and system can improve the rate of generating true random numbers based on the stability of the optical frequency comb spectrum and the large spectrum range, and can reduce the selection cost of wavelength division devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 It is a flowchart of an embodiment of a method for generating true random numbers based on an optical frequency comb according to the present disclosure;

[0020] Figure 2 A schematic diagram of a process of obtaining an optical frequency comb and performing wavelength division processing in one embodiment of a true random number generation method based on an optical frequency comb according to the present disclosure;

[0021] Figure 3 A schematic diagram of a process for obtaining a laser signal with random light intensity in one embodiment of a true random number generation method based on an optical frequency comb according to the present disclosure;

[0022] Figure 4 It is a module schematic diagram of an embodiment of a true random number generation system based on an optical frequency comb according to the present disclosure;

[0023] Figure 5 It is a module diagram of another embodiment of a true random number generation system based on an optical frequency comb according to the present disclosure. DETAILED DESCRIPTION

[0024] The present disclosure is described more fully below with reference to the accompanying drawings, in which exemplary embodiments of the present disclosure are described. The technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure. The technical solutions of the present disclosure are described in many aspects below in conjunction with various figures and embodiments.

[0025] The terms "first", "second", etc. in the following text are only used to distinguish between the two and have no other special meanings.

[0026] The existing true random number generation schemes based on optical frequency combs have the following main shortcomings: 1. Multiple lasers are used as light sources to generate true random numbers in parallel. This scheme has limited efficiency in improving true random number generation and is relatively costly; 2. Supercontinuum or multi-longitudinal mode lasers are used as light sources. The distance between the spectra of these two light sources is uncertain, and it is difficult to select a suitable wavelength division device to separate the single longitudinal mode laser.

[0027] Figure 1 FIG. 1 is a flow chart of an embodiment of a method for generating true random numbers based on an optical frequency comb according to the present disclosure, as shown in FIG. Figure 1 As shown:

[0028] Step 101: Use a fiber laser to generate an optical frequency comb with a preset repetition frequency.

[0029] Step 102: Split the laser signal output by the optical frequency comb into a plurality of laser component signals with different frequencies by using a wavelength division device.

[0030] Step 103: Phase conversion and coupling processing are performed on multiple laser component signals respectively through multiple interferometer modules to obtain multiple laser signals with random light intensities.

[0031] In one embodiment, a plurality of interferometer modules are provided, each interferometer module corresponds to a laser component signal, and each interferometer module performs phase transformation and coupling processing on the corresponding laser component signal to obtain a laser signal with random light intensity.

[0032] Step 104: convert multiple laser signals with random light intensities into multiple random analog electrical signals through a photodetector. The photodetector may be any of a variety of existing photodetectors.

[0033] Step 105: Generate and output a true random number based on a plurality of random analog electrical signals through a data processing module.

[0034] The true random number generation method based on the optical frequency comb in the above embodiment can reduce the selection cost of wavelength division devices while improving the true random number generation rate by leveraging the stability of the optical frequency comb spectrum and the extremely large spectrum range.

[0035] Figure 2 FIG. 1 is a flow chart of obtaining an optical frequency comb and performing wavelength division processing in one embodiment of a true random number generation method based on an optical frequency comb according to the present disclosure, as shown in FIG. Figure 2 As shown:

[0036] Step 201, using a fiber laser as a laser light source.

[0037] Step 202, obtaining an optical frequency comb by controlling the repetition frequency and carrier envelope frequency shift of the femtosecond laser generated by the laser light source; wherein the optical frequency comb outputs a femtosecond pulse laser with a repetition frequency in the time domain.

[0038] In one embodiment, there may be multiple types of fiber lasers, such as dispersion-managed mode-locked fiber lasers. With a dispersion-managed mode-locked fiber laser as a laser light source, the repetition frequency and carrier envelope frequency shift of the femtosecond laser are precisely controlled. The repetition frequency and carrier envelope frequency shift of the femtosecond laser generated by the laser light source may be controlled using existing control methods to obtain a stable optical frequency comb, ensuring that the optical frequency comb appears as a femtosecond pulse laser with a stable repetition frequency in the time domain.

[0039] Step 203 , splitting the femtosecond pulse laser output by the optical frequency comb into a plurality of first single longitudinal mode laser beams with different wavelengths through a wavelength division device.

[0040] In one embodiment, based on the distance between adjacent spectrums and spectrum width of the optical frequency comb, a wavelength division device for wavelength division processing of the femtosecond pulse laser output by the optical frequency comb is selected. By measuring the distance between adjacent spectrums and spectrum width of the optical frequency comb, the positions of other spectrums are calculated, and appropriate filters and wavelength division devices are selected to obtain multiple beams of single longitudinal mode lasers with different wavelengths.

[0041] In one embodiment, the interferometer module includes a first coupler, an interferometer unit, and a second coupler. The first coupler, the interferometer unit, and the second coupler may be existing interferometer units and couplers. Figure 3 FIG. 1 is a flow chart of obtaining a laser signal with random light intensity in one embodiment of a true random number generation method based on an optical frequency comb according to the present disclosure, as shown in FIG. Figure 3 As shown:

[0042] Step 301: input a first single longitudinal mode laser into a first coupler to obtain two second single longitudinal mode laser beams output by the first coupler.

[0043] Step 302: input two second single longitudinal mode laser beams into an interferometer unit. The interferometer unit is used to change the phase of one second single longitudinal mode laser beam, while not processing the other second single longitudinal mode laser beam.

[0044] Step 303: couple two second single longitudinal mode laser beams through a second coupler to obtain a laser signal with random light intensity.

[0045] In one embodiment, a first single longitudinal mode laser beam is input into a 1:1 first coupler to obtain two second single longitudinal mode laser beams, one of which is input into a temperature-sensitive interferometer (such as PLC-MZI, etc.) to change the phase of the second single longitudinal mode laser beam, while the other second single longitudinal mode laser beam is not processed. The two second single longitudinal mode laser beams are coupled through a 1:1 second coupler to finally obtain a laser beam with random light intensity.

[0046] The data processing module includes an analog-to-digital conversion device, etc., which converts multiple random analog electrical signals into multiple random digital electrical signals, generates true random numbers based on the multiple random digital electrical signals, and outputs them.

[0047] In one embodiment, Figure 4 As shown, the present disclosure provides a true random number generation system based on an optical frequency comb, comprising: a fiber laser 41, a wavelength division device 42, an interferometer module 43, a photodetector 44 and a data processing module 45. The fiber laser 41 generates an optical frequency comb with a preset repetition frequency. The wavelength division device 42 divides the laser signal output by the optical frequency comb into a plurality of laser component signals with different frequencies.

[0048] A plurality of interferometer modules 43 are provided, each of which corresponds to a laser component signal, and each of which performs phase transformation and coupling processing on the corresponding laser component signal to obtain a laser signal with random light intensity. The plurality of interferometer modules 43 respectively perform phase transformation and coupling processing on the plurality of laser component signals to obtain a plurality of laser signals with random light intensity. The photodetector 44 converts the plurality of laser signals with random light intensity into a plurality of random analog electrical signals. The data processing module 45 generates and outputs true random numbers based on the plurality of random analog electrical signals.

[0049] In one embodiment, the fiber laser 41 is used as a laser light source, and an optical frequency comb is obtained by controlling the repetition frequency and carrier envelope frequency shift of the femtosecond laser generated by the laser light source; wherein the optical frequency comb outputs a femtosecond pulse laser with a repetition frequency in the time domain. The wavelength division device 42 divides the femtosecond pulse laser output by the optical frequency comb into multiple beams of first single longitudinal mode lasers with different wavelengths.

[0050] The fiber laser 41 includes a dispersion-managed mode-locked fiber laser, etc. A dispersion-managed soliton passive mode-locked fiber laser is used as a light source (two-dimensional nanomaterials are used as saturable absorbers, such as black scale, etc., which can further reduce costs), and an optical frequency comb is output by locking the repetition frequency and carrier envelope frequency shift of femtosecond pulses, ensuring that the optical frequency comb appears as a femtosecond pulse laser with a stable repetition frequency in the time domain.

[0051] The high peak power of dispersion-managed solitons can improve the utilization of pulses. The uniform distribution and fixed position of optical frequency combs in the frequency domain can reduce the selection cost of wavelength division devices in high-speed true random number generators and improve the utilization of spectrum. The extremely wide spectrum width of optical frequency combs can increase the generation rate of true random numbers.

[0052] In one embodiment, Figure 5 As shown, three interferometer modules are provided, each interferometer module corresponds to a beam of first single longitudinal mode laser, and each interferometer module performs phase transformation and coupling processing on the corresponding first single longitudinal mode laser to obtain a laser signal with random light intensity. The three interferometer modules respectively include first couplers 4311, 4321, 4331, interferometer units 4312, 4322, 4332 and second couplers 4313, 4323, 4333. The following is an explanation using an interferometer module:

[0053] The first coupler 4311 divides the input first single longitudinal mode laser into two second single longitudinal mode laser beams; the interferometer unit 4312 receives the two second single longitudinal mode laser beams, changes the phase of one second single longitudinal mode laser beam, and does not process the other second single longitudinal mode laser beam; the second coupler 4313 couples the two second single longitudinal mode laser beams to obtain a laser signal with random light intensity.

[0054] The data processing module 45 includes an analog-to-digital conversion device, which converts a plurality of random analog electrical signals into a plurality of random digital electrical signals, generates true random numbers based on the plurality of random digital electrical signals, and outputs the generated true random numbers.

[0055] In one embodiment, a femtosecond fiber laser is used as a laser light source, and a stable optical frequency comb can be obtained by precisely controlling the repetition frequency (i.e., the number of pulses output by the laser per unit time) and the carrier envelope frequency shift of the femtosecond laser. For example, an optical frequency comb with a spectral width of 1000nm and a repetition frequency of 300MHz is obtained, and the laser outputs 3*10 8 By taking out a single longitudinal mode laser beam every 1nm, 1000 single longitudinal mode laser beams can be taken out at the same time. After these single longitudinal mode laser beams are processed by the temperature-sensitive interferometer, photoelectric detector and data processing module, 1000 true random numbers can be obtained at the same time. Theoretically, the device can generate 3*10 11 A true random number.

[0056] The true random number generation method and system based on the optical frequency comb provided in the above-mentioned embodiment obtains multiple random optical signals by inputting each frequency component of the optical frequency comb into an interferometer, converts the random optical signal into a random electrical signal through a photodetector, and converts the random analog electrical signal into a random digital electrical signal through an analog-to-digital conversion device; based on the stability of the optical frequency comb spectrum and the large spectrum range, the true random number generation rate can be improved, and the selection cost of wavelength division devices can be reduced.

[0057] The method and system of the present disclosure may be implemented in many ways. For example, the method and system of the present disclosure may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above order of steps for the method is for illustration only, and the steps of the method of the present disclosure are not limited to the order specifically described above, unless otherwise specifically stated. In addition, in some embodiments, the present disclosure may also be implemented as a program recorded in a recording medium, which includes machine-readable instructions for implementing the method according to the present disclosure. Therefore, the present disclosure also covers a recording medium storing a program for executing the method according to the present disclosure.

[0058] The description of the present disclosure is given for the purpose of illustration and description, and is not intended to be exhaustive or to limit the present disclosure to the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present disclosure, and to enable those of ordinary skill in the art to understand the present disclosure and thereby design various embodiments with various modifications suitable for specific uses.

Claims

1. A true random number generation method based on an optical frequency comb, comprising: Using a fiber laser to generate an optical frequency comb with a preset repetition rate; The laser signal output by the optical frequency comb is divided into a plurality of laser component signals with different frequencies by a wavelength division device, comprising: Splitting the femtosecond pulse laser output by the optical frequency comb into a plurality of first single longitudinal mode laser beams with different wavelengths through the wavelength division device; Performing phase transformation and coupling processing on the multiple laser component signals respectively through multiple interferometer modules to obtain multiple laser signals with random light intensities; The interferometer module includes: a first coupler, an interferometer unit, and a second coupler; the phase transformation and coupling processing of the multiple laser component signals are performed by the multiple interferometer modules to obtain multiple laser signals with random light intensities, including: Inputting the first single longitudinal mode laser beam into the first coupler to obtain two second single longitudinal mode laser beams output by the first coupler; inputting the two second single longitudinal mode laser beams into the interferometer unit, wherein the interferometer unit is used to change the phase of one second single longitudinal mode laser beam and not process the other second single longitudinal mode laser beam; coupling the two second single longitudinal mode laser beams through the second coupler to obtain a laser signal with random light intensity; Converting the plurality of laser signals with random light intensities into a plurality of random analog electrical signals through a photodetector; A true random number is generated and outputted based on the multiple random analog electrical signals through a data processing module.

2. The method of claim 1, wherein generating an optical frequency comb having a preset repetition frequency using a fiber laser comprises: Using the fiber laser as a laser light source; The optical frequency comb is obtained by controlling the repetition frequency and carrier envelope frequency shift of the femtosecond laser generated by the laser light source; wherein the optical frequency comb outputs femtosecond pulse laser of the repetition frequency in the time domain.

3. The method of claim 2, wherein: The fiber laser comprises: a dispersion-managed mode-locked fiber laser.

4. The method of claim 2, further comprising: The wavelength division device for performing wavelength division processing on the femtosecond pulse laser output by the optical frequency comb is selected based on the distance between adjacent frequency spectra of the optical frequency comb and the spectrum width.

5. The method of claim 4, wherein: The data processing module comprises: an analog-to-digital conversion device; the data processing module generates true random numbers based on the multiple random analog electrical signals and outputs the numbers, comprising: The multiple random analog electrical signals are converted into the multiple random digital electrical signals by the analog-to-digital conversion device, and true random numbers are generated and output based on the multiple random digital electrical signals.

6. A true random number generation system based on an optical frequency comb, comprising: a fiber laser for generating an optical frequency comb with a preset repetition rate; A wavelength division device, used for dividing the laser signal output by the optical frequency comb into a plurality of laser component signals with different frequencies; Wherein, the wavelength division device is used to divide the femtosecond pulse laser output by the optical frequency comb into multiple beams of first single longitudinal mode lasers with different wavelengths; A plurality of interferometer modules, used to respectively perform phase conversion and coupling processing on the plurality of laser component signals to obtain a plurality of laser signals with random light intensities; Wherein, the interferometer module comprises: a first coupler, an interferometer unit and a second coupler; The first coupler is used to split the input first single longitudinal mode laser into two second single longitudinal mode laser beams; The interferometer unit is used to receive the two second single longitudinal mode laser beams, change the phase of one second single longitudinal mode laser beam, and not process the other second single longitudinal mode laser beam; The second coupler is used to couple the two second single longitudinal mode laser beams to obtain a laser signal with random light intensity; A photoelectric detector, used for converting the plurality of laser signals with random light intensities into a plurality of random analog electrical signals; The data processing module is used to generate and output true random numbers based on the multiple random analog electrical signals.

7. The system of claim 6, wherein: The fiber laser is used as a laser light source, and the optical frequency comb is obtained by controlling the repetition frequency and carrier envelope frequency shift of the femtosecond laser generated by the laser light source; wherein the optical frequency comb outputs femtosecond pulse laser of the repetition frequency in the time domain.

8. The system of claim 7, wherein: The fiber laser comprises: a dispersion-managed mode-locked fiber laser.

9. The system of claim 7, wherein: The data processing module includes: an analog-to-digital conversion device; The analog-to-digital conversion device is used to convert the multiple random analog electrical signals into the multiple random digital electrical signals, generate true random numbers based on the multiple random digital electrical signals, and output them.

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