Quantum random number generator based on XPM light sampling

Abstract

The utility model discloses a quantum random number generator based on XPM light sampling. The quantum random number generator comprises an entropy source, an M-Z type light sampling module, a detection module and a post-processing module, wherein the M-Z type optical sampling module comprises a probe light generating unit, a first optical coupler, a second optical coupler, a third optical coupler, a first semiconductor optical amplifier, a second semiconductor optical amplifier and a first band-pass filter. The utility model discloses a quantum random number generator based on XPM optical sampling, which adopts an M-Z type optical sampling module to carry out nonlinear all-optical sampling, compared with an electronic device, the quantum random number generator has higher processing speed, can realize 40Gbit / s high-speed safe random sequence generation, and effectively improves the generation rate of quantum random numbers; the high-speed analog-to-digital converter can be optimized and eliminated, the system cost is effectively reduced, and the high practical value is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to quantum random number generator and quantum password cloud technical field, concretely relates to a kind of quantum random number generator based on XPM light sampling. BACKGROUND

[0002] Quantum random number generator (Quantum Random Number Generator, QRNG) is the only theoretically provable true random number generator so far, based on quantum effect, theoretically proven to have unpredictable characteristics, distinguished from pseudo-random number generator and classical physical random number generator, the latter two are based on complex algorithm and process easy-to-analog classical physical phenomenon, quantum random number generator has higher security.

[0003] Semiconductor optical amplifier (semiconductor optical amplifier, SOA) is applied in all-optical signal processing with its good nonlinear effect and larger optical power efficiency.Cross-phase modulation (Cross-Phase Modulation, XPM) is a kind of nonlinear optical effect, when two or more light waves interact in the same nonlinear medium, the phase of one light will change due to the existence of another light, in SOA and other nonlinear effect obvious devices, XPM effect is very significant.

[0004] The sampling quantization and post-processing module in existing quantum random number generator often uses electronic equipment, and at present, due to the development of technology, there is an "electronic bottleneck" in analog-to-digital converter, that is, the sampling rate and accuracy of analog-to-digital converter are difficult to improve, which will affect the quantization accuracy, sampling rate and analog input bandwidth, greatly limiting the generation rate of random sequence. Therefore, the rate of generating quantum random number by the existing quantum random number generator is not high enough. UTILITY MODEL CONTENT

[0005] The utility model discloses in order to solve the problem of the rate of generating quantum random number by the existing quantum random number generator is not high enough, propose a kind of quantum random number generator based on XPM light sampling.

[0006] To achieve the above object, the technical scheme adopted by the utility model is as follows:

[0007] A kind of quantum random number generator based on XPM light sampling, including entropy source, M-Z type light sampling module, detection module and post-processing module;Wherein,

[0008] The M-Z type light sampling module includes probe light generation unit, first optical coupler, second optical coupler, third optical coupler, first semiconductor optical amplifier, second semiconductor optical amplifier and first band-pass filter;

[0009] The output end of the entropy source is connected with the input end of the second optical coupler and the input end of the second semiconductor optical amplifier respectively through the first optical coupler, the output end of the second optical coupler is connected with the input end of the first semiconductor optical amplifier, the output end of the first semiconductor optical amplifier and the output end of the second semiconductor optical amplifier are connected with the input end of the third optical coupler respectively, the output end of the third optical coupler is connected with the input end of the detection module through the first band-pass filter, and the output end of the detection module is connected with the input end of the post-processing module.

[0010] In the above scheme, the nonlinear all-optical sampling is carried out by using the M-Z type optical sampling module, which has a high processing speed compared with electronic devices, can realize 40Gbit / s high-speed safe random sequence generation, and effectively improves the generation rate of quantum random numbers; and without using a high-speed analog-to-digital converter, the system cost can be effectively reduced, and the method has high practical value.

[0011] Preferably, the entropy source comprises a signal light generating unit, a second band-pass filter, an erbium-doped fiber amplifier and an optical isolator.

[0012] The output end of the signal light generating unit is connected with the input end of the second band-pass filter, the output end of the second band-pass filter is connected with the input end of the erbium-doped fiber amplifier, the output end of the erbium-doped fiber amplifier is connected with the input end of the optical isolator, and the output end of the optical isolator is connected with the input end of the first optical coupler.

[0013] Preferably, the detection module comprises a photodetector, a transimpedance amplifier and an analog-to-digital converter.

[0014] The output end of the first band-pass filter is connected with the input end of the photodetector, the output end of the photodetector is connected with the input end of the transimpedance amplifier, the output end of the transimpedance amplifier is connected with the input end of the analog-to-digital converter, and the output end of the analog-to-digital converter is connected with the input end of the post-processing module.

[0015] Preferably, the detection light generating unit is an optical frequency comb.

[0016] Preferably, the bandwidth of the optical frequency comb is 40GHz.

[0017] Preferably, the center wavelength of the first band-pass filter is 1550nm, and the bandwidth is 20nm.

[0018] Preferably, the signal light generating unit is a superluminescent diode.

[0019] Preferably, the center wavelength of the laser emitted by the superluminescent diode is 1550nm.

[0020] Preferably, the second band-pass filter has a center wavelength of 1550nm and a bandwidth of 20nm.

[0021] Preferably, the photoelectric detector has a bandwidth of 40GHz.

[0022] The beneficial technical effects of the present application are as follows:

[0023] The utility model provides a quantum random number generator based on XPM light sampling, through adopting M -Z type light sampling module carries out nonlinear all -optical sampling, compared with electronic device, has higher processing speed, can realize 40Gbit / s high -speed safe random sequence generation, effectively improves the generation rate of quantum random number, need not to adopt high -speed analog -to -digital converter, effectively reduces the system cost, has very high practical value. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is the whole module connection schematic drawing of the utility model;

[0025] Figure 2 It is the module connection schematic drawing of entropy source in the utility model;

[0026] Figure 3 It is the module connection schematic drawing of detection module in the utility model;

[0027] Wherein: 1, entropy source;11, signal light generating unit;12, second band-pass filter;13, erbium-doped fiber amplifier;14, optical isolator;2, M-Z type light sampling module;21, probe light generating unit;22, first optical coupler;23, second optical coupler;24, third optical coupler;25, first semiconductor optical amplifier;26, second semiconductor optical amplifier;27, first band-pass filter;3, detection module;31, photoelectric detector;32, transimpedance amplifier;33, analog-to-digital converter;4, post-processing module. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the utility model more clearly, the following will be further detailed with examples, but the scope of the utility model claimed is not limited to the following specific examples.

[0029] Example 1

[0030] As Figure 1 shown, a quantum random number generator based on XPM light sampling includes entropy source 1, M-Z type light sampling module 2, detection module 3 and post-processing module 4;Wherein,

[0031] The M-Z type light sampling module 2 comprises a probe light generating unit 21, a first optical coupler 22, a second optical coupler 23, a third optical coupler 24, a first semiconductor optical amplifier 25, a second semiconductor optical amplifier 26 and a first band-pass filter 27.

[0032] The output end of the entropy source 1 is connected with the input end of the second optical coupler 23 and the input end of the second semiconductor optical amplifier 26 through the first optical coupler 22, the output end of the probe light generating unit 21 is connected with the input end of the second optical coupler 23, the output end of the second optical coupler 23 is connected with the input end of the first semiconductor optical amplifier 25, the output end of the first semiconductor optical amplifier 25 and the output end of the second semiconductor optical amplifier 26 are respectively connected with the input end of the third optical coupler 24, the output end of the third optical coupler 24 is connected with the input end of the probe module 3 through the first band-pass filter 27, and the output end of the probe module 3 is connected with the input end of the post-processing module 4.

[0033] In the specific implementation process, the nonlinear all-optical sampling is performed by using the M-Z type light sampling module 2, which has a higher processing speed compared with electronic devices, can realize 40Gbit / s high-speed secure random sequence generation, and effectively improves the generation rate of quantum random numbers; and without using a high-speed analog-to-digital converter 33, the system cost can be effectively reduced, and the quantum random number generator has high practical value.

[0034] Embodiment 2

[0035] A quantum random number generator based on XPM light sampling comprises an entropy source 1, an M-Z type light sampling module 2, a probe module 3 and a post-processing module 4; wherein,

[0036] More specifically, as shown in Figure 2 The entropy source 1 comprises a signal light generating unit 11, a second band-pass filter 12, an erbium-doped fiber amplifier 13 and an optical isolator 14.

[0037] The output end of the signal light generating unit 11 is connected with the input end of the second band-pass filter 12, the output end of the second band-pass filter 12 is connected with the input end of the erbium-doped fiber amplifier 13, the output end of the erbium-doped fiber amplifier 13 is connected with the input end of the optical isolator 14, and the output end of the optical isolator 14 is connected with the input end of the first optical coupler 22.

[0038] More specifically, the signal light generating unit 11 is a super radiation light emitting diode.

[0039] More specifically, the central wavelength of the laser emitted by the super radiation light emitting diode is 1550nm.

[0040] More specifically, the second band-pass filter 12 has a center wavelength of 1550 nm and a bandwidth of 20 nm.

[0041] In the embodiment, the light signal emitted by the superluminescent diode has a center wavelength of 1550 nm, is filtered by the second band-pass filter 12 having a center wavelength of 1550 nm and a bandwidth of 20 nm, is amplified by the erbium-doped fiber amplifier 13, and then enters the M-Z optical sampling module 2 through the optical isolator 14.

[0042] The superluminescent diode (SLD) is a high-stability light source with high output power and wide spectral range, and its light-emitting principle is a directional radiation phenomenon under strong excitation, that is, when the excitation density is high enough, the spontaneously emitted photons are amplified and multiplied in an avalanche manner, thus having amplifier spontaneous emission (ASE) noise, which is a quantum effect and can ensure the randomness of generated random numbers and can be applied to the generation of quantum random numbers.

[0043] The ASE noise spectrum of the superluminescent diode is wide, which is easy to saturate the photodetector 31, so the second band-pass filter 12 is used to filter the superluminescent diode.

[0044] In the embodiment, the ASE noise satisfies the Bose-Einstein distribution:

[0045]

[0046] where n is the probability of calculating n photons in the average detection time, which is defined as the inverse of the bandwidth of the detector, is the average number of photons in the same time interval;

[0047] The ASE light field containing more independent modes can be represented by the M-fold degenerate Bose-Einstein distribution:

[0048]

[0049] where M is the mode number of the light field, Γ(x) is the gamma function, and n is the average number of photons in each mode.

[0050] The M-Z optical sampling module 2 includes a probe light generating unit 21, a first optical coupler 22, a second optical coupler 23, a third optical coupler 24, a first semiconductor optical amplifier 25, a second semiconductor optical amplifier 26, and a first band-pass filter 27.

[0051] The output end of the entropy source 1 is connected with the input end of the second optical coupler 23 and the input end of the second semiconductor optical amplifier 26 through the first optical coupler 22 respectively, the output end of the probe light generating unit 21 is connected with the input end of the second optical coupler 23, the output end of the second optical coupler 23 is connected with the input end of the first semiconductor optical amplifier 25, the output end of the first semiconductor optical amplifier 25 and the output end of the second semiconductor optical amplifier 26 are connected with the input end of the third optical coupler 24 respectively, the output end of the third optical coupler 24 is connected with the input end of the probe module 3 through the first band-pass filter 27, and the output end of the probe module 3 is connected with the input end of the post-processing module 4.

[0052] More specifically, the probe light generating unit 21 is an optical frequency comb.

[0053] More specifically, the bandwidth of the optical frequency comb is 40GHz.

[0054] In the specific implementation process, the optical frequency comb is generated by a mode-locked laser, which can generate a series of equidistant discrete frequency spectral lines. Compared with the traditional electronic clock, when the optical frequency comb is used as a time reference or a sampling clock, its femtosecond-level ultra-low phase jitter is particularly prominent, which is usually 3 to 4 orders of magnitude lower. The measurement and sampling using the optical frequency comb can achieve an unprecedented effective quantization resolution, that is, the effective number of bits (ENOB) is significantly improved, and the available input analog signal bandwidth is greatly expanded.

[0055] More specifically, the center wavelength of the first band-pass filter 27 is 1550nm, and the bandwidth is 20nm.

[0056] In the specific implementation process, the high-speed sampling pulse generated by the optical frequency comb is used as the probe light.

[0057] The signal light output by the entropy source 1 is divided into two paths through the first optical coupler 22, one of which is combined with the probe light through the second optical coupler 23 and input into the first semiconductor optical amplifier 25, and the other is directly input into the second semiconductor optical amplifier 26, and the optical sampling is carried out based on the cross-phase modulation, and finally the probe light is filtered out through the first band-pass filter 27 to obtain the sampling pulse.

[0058] The SOA has a significant nonlinear effect, and the nonlinear optical sampling system based on the SOA utilizes the saturation effect of the active region. When the sampling light is incident, the gain is saturated, and the carrier density of the active region and the refractive index of the waveguide change. Compared with other nonlinear optical sampling systems, it has the advantages of polarization independence, short gain recovery time and compact structure.

[0059] The optical sampling based on cross phase modulation utilizes the nonlinear effect of the SOA, in which the change of carrier density will cause the change of refractive index, and then cause the change of phase. Firstly, the energy of the probe light is set to be significantly higher than that of the signal light, at this time, the carrier concentration in the SOA will fluctuate with the probe light, therefore, the refractive index of the SOA will be affected by the input probe light and change, the change of the refractive index causes the change of the phase difference of the two sampling lights, and the change of the phase difference is converted into the change of the light intensity in the interference process, thereby realizing the interference modulation of the signal light intensity.

[0060] When only the signal light is input, the gain of the SOA is the small signal gain, the two signal lights produce equal phase changes after passing through the SOA, the phase difference is 0, when reaching the third optical coupler 24, the two signal lights interfere and cancel each other, and no light is output from the light path;

[0061] When the probe light is input, the carrier in the SOA is quickly depleted, and reaches the gain saturation state, the two signal lights will produce different phase changes, and there is a phase difference, when reaching the third optical coupler 24, the two signal lights interfere and add up, and the sampling signal is output.

[0062] More specifically, as shown in Figure 3 the probe module 3 comprises a photodetector 31, a transimpedance amplifier 32 and an analog-to-digital converter 33;

[0063] The output end of the first band-pass filter 27 is connected with the input end of the photodetector 31, the output end of the photodetector 31 is connected with the input end of the transimpedance amplifier 32, the output end of the transimpedance amplifier 32 is connected with the input end of the analog-to-digital converter 33, and the output end of the analog-to-digital converter 33 is connected with the input end of the post-processing module 4.

[0064] More specifically, the bandwidth of the photodetector 31 is 40GHz.

[0065] In the specific implementation process, the output result of the photodetector 31 is input into the analog-to-digital converter 33 for quantization, since the analog-to-digital converter 33 of the embodiment only plays a quantization role, it is not necessary to purchase a high-speed ADC, thereby effectively reducing the system cost, and having high practical value, finally, the final random number is output after post-processing, and the high-speed secure random sequence generation of 40Gbit / s can be realized.

[0066] According to the disclosure and teaching of the above description, the skilled in the art of the utility model can also change and modify the above embodiments. Therefore, the utility model is not limited to the specific embodiments disclosed and described above, and some modifications and changes of the utility model should fall within the protection scope of the claims of the utility model. In addition, although some specific terms are used in the specification, these terms are only for convenience and do not constitute any limitation on the utility model.

Claims

1. A quantum random number generator based on XPM optical sampling, characterized in that, The entropy source, the M-Z type optical sampling module, the detection module and the post-processing module are included. The M-Z type optical sampling module includes a detection light generating unit, a first optical coupler, a second optical coupler, a third optical coupler, a first semiconductor optical amplifier, a second semiconductor optical amplifier and a first band-pass filter. The output end of the entropy source is connected with the input end of the second optical coupler and the input end of the second semiconductor optical amplifier through the first optical coupler, the output end of the detection light generating unit is connected with the input end of the second optical coupler, the output end of the second optical coupler is connected with the input end of the first semiconductor optical amplifier, the output end of the first semiconductor optical amplifier and the output end of the second semiconductor optical amplifier are connected with the input end of the third optical coupler respectively, the output end of the third optical coupler is connected with the input end of the detection module through the first band-pass filter, and the output end of the detection module is connected with the input end of the post-processing module.

2. The quantum random number generator based on XPM optical sampling according to claim 1, characterized in that, The entropy source includes a signal light generating unit, a second band-pass filter, an erbium-doped fiber amplifier and an optical isolator. The output end of the signal light generating unit is connected with the input end of the second band-pass filter, the output end of the second band-pass filter is connected with the input end of the erbium-doped fiber amplifier, the output end of the erbium-doped fiber amplifier is connected with the input end of the optical isolator, and the output end of the optical isolator is connected with the input end of the first optical coupler.

3. The quantum random number generator based on XPM optical sampling according to claim 1, characterized in that, The detection module includes a photodetector, a transimpedance amplifier and an analog-to-digital converter. The output end of the first band-pass filter is connected with the input end of the photodetector, the output end of the photodetector is connected with the input end of the transimpedance amplifier, the output end of the transimpedance amplifier is connected with the input end of the analog-to-digital converter, and the output end of the analog-to-digital converter is connected with the input end of the post-processing module.

4. The quantum random number generator based on XPM optical sampling according to claim 1, characterized in that, The detection light generating unit is an optical frequency comb.

5. The quantum random number generator based on XPM optical sampling according to claim 4, characterized in that, The bandwidth of the optical frequency comb is 40GHz.

6. The quantum random number generator based on XPM optical sampling according to claim 1, characterized in that, The center wavelength of the first band-pass filter is 1550nm, and the bandwidth is 20nm.

7. The quantum random number generator based on XPM optical sampling according to claim 2, characterized in that, The signal light generating unit is a super radiation light emitting diode.

8. The quantum random number generator based on XPM optical sampling according to claim 7, characterized in that, The center wavelength of the laser emitted by the super radiation light emitting diode is 1550nm.

9. The quantum random number generator based on XPM optical sampling according to claim 7, characterized in that, The center wavelength of the second band-pass filter is 1550nm, and the bandwidth is 20nm.

10. The quantum random number generator based on XPM optical sampling according to claim 3, characterized in that, The bandwidth of the photodetector is 40GHz.

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