Single photon source system, single photon source generation method and optical equipment

Abstract

The invention provides a single photon source system, a single photon source generation method and optical equipment, and is applied to the technical field of optics, the system comprises a first module, the first module comprises a pulse processing unit and a micro-ring resonant cavity, and the output end of the pulse processing unit is connected with the input end of the micro-ring resonant cavity; wherein the pulse processing unit is used for generating a first pulse and a second pulse of a target phase difference, and generating a target pulse by superposing the first pulse and the second pulse; and the micro-ring resonant cavity is used for enabling the target pulse to resonate in the micro-ring resonant cavity to generate an announcement type single photon source. According to the system, the target pulse is obtained by superposing the first pulse and the second pulse with the target phase difference, and then the obtained target pulse is resonated in the micro-ring resonant cavity to generate the declaring type single photon source, so that the purity of the generated declaring type single photon source can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of optical technology, and in particular to a single-photon source system, a single-photon source generation method and an optical device. Background Art

[0002] Single photon sources are core components in quantum communication and quantum computing systems. The development trend of quantum communication and quantum computing requires single photon sources to have advantages such as high purity, high brightness and indistinguishability. The existing single photon source system is a spontaneous four-wave mixing photon source of a traditional microring resonator. The single photon source generated based on spontaneous four-wave mixing has high indistinguishability, but the photon purity of the generated single photon source is low and cannot meet the application requirements of high-precision quantum information technology.

[0003] Application Contents

[0004] The embodiments of the present application provide a single-photon source system, a single-photon source generation method and an optical device to solve the problem of low photon purity of single-photon sources generated in existing single-photon source systems.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a single photon source system, the single photon source system comprising:

[0007] A first module, wherein the first module comprises a pulse processing unit and a micro-ring resonant cavity, wherein an output end of the pulse processing unit is connected to an input end of the micro-ring resonant cavity;

[0008] Wherein, the pulse processing unit is used to generate a first pulse and a second pulse with a target phase difference, and generate a target pulse by superimposing the first pulse and the second pulse;

[0009] The micro-ring resonant cavity is used to make the target pulse resonate in the micro-ring resonant cavity to generate a declared single photon source.

[0010] Optionally, the single photon source system further comprises at least one of the following:

[0011] A separation module, a detection module, a buffer module, a driving module and an output module, wherein the input end of the separation module is connected to the output end of the microring resonant cavity, the first output end and the second output end of the separation module are respectively connected to the input end of the detection module and the input end of the buffer module, the output end of the detection module is connected to the input end of the driving module, the output end of the driving module is connected to the control end of the output module, and the output end of the buffer module is connected to the input end of the output module, wherein:

[0012] The separation module is used to separate the announced single photon source into idler photons and signal photons, and output them through the first output end and the second output end of the separation module respectively;

[0013] The detection module is used for sending a first electrical signal to the driving module when the idler photon is detected;

[0014] The buffer module is used to buffer the signal photons;

[0015] The driving module is used to drive the optical switch when receiving the first electrical signal;

[0016] The output module is used to output the signal photons under the drive of the driving module.

[0017] Optionally, the single photon source system further comprises:

[0018] Laser and beam splitter, where

[0019] The laser is used to generate a third pump pulse;

[0020] The beam splitter is used to split a beam of the third pump pulse into N fourth pump pulses, where N is an integer greater than 1;

[0021] The single-photon source system includes N first modules, and each fourth pump pulse is input into one first module respectively; a pulse processing unit is used to convert one fourth pump pulse into the first pulse and the second pulse.

[0022] Optionally, the single photon source system comprises a first port and a second port, wherein:

[0023] The first port is used to output a target signal photon, wherein the target signal photon is a signal photon in a first announced single-photon source, and the first announced single-photon source is one of at least one announced single-photon source generated by N first modules;

[0024] The second port is used to output other photons in the at least one announced single-photon source except the target signal photon.

[0025] Optionally, the pulse processing unit is a waveform shaper;

[0026] The waveform shaper is used for converting the input fourth pump pulse into the first pulse and the second pulse having the target phase difference, and obtaining the target pulse by adjusting the waveforms of the first pulse and the second pulse.

[0027] Optionally, the pulse processing unit is an unequal-arm Mach-Zehnder interferometer AMZI;

[0028] The AMZI is used to divide the input fourth pump pulse into two pump pulses, and obtain the first pulse and the second pulse by controlling the relative phase difference and relative intensity of the two pump pulses; and generate the target pulse by superimposing the first pulse and the second pulse.

[0029] In a second aspect, an embodiment of the present application further provides a single photon source generation method, the single photon source generation method comprising:

[0030] Generate a first pulse and a second pulse with a target phase difference, and generate a target pulse by superimposing the first pulse and the second pulse;

[0031] By resonating the target pulse, a propagation-type single photon source is generated.

[0032] Optionally, after causing the target pulse to resonate and generate a declared single photon source, the method further comprises:

[0033] Separating the announced single photon source into idler photons and signal photons, wherein the idler photons enter the detection module and the signal photons enter the buffer module;

[0034] When the idler photon is detected, the signal photon is output.

[0035] Optionally, before generating the first pulse and the second pulse with a target phase difference and generating the target pulse by superimposing the first pulse and the second pulse, the method further includes:

[0036] dividing a beam of third pump pulses into N fourth pump pulses, where N is an integer greater than 1;

[0037] Respectively converting each of the fourth pump pulses into the first pulse and the second pulse to obtain N channels of the first pulse and the second pulse;

[0038] Generating a target pulse by superimposing the first pulse and the second pulse comprises:

[0039] Generate a target pulse by superimposing each of the first pulse and the second pulse to obtain N target pulses;

[0040] The method of generating a single photon source by resonating the target pulse comprises:

[0041] By resonating each of the target pulses, respectively, at least one declared single photon source is generated.

[0042] In a third aspect, an embodiment of the present application further provides an optical device, which includes the single photon source system as described above.

[0043] The single-photon source system of the embodiment of the present application includes a first module, wherein the first module includes a pulse processing unit and a micro-ring resonant cavity, wherein the output end of the pulse processing unit is connected to the input end of the micro-ring resonant cavity; wherein the pulse processing unit is used to generate a first pulse and a second pulse with a target phase difference, and to generate a target pulse by superimposing the first pulse and the second pulse; and the micro-ring resonant cavity is used to make the target pulse resonate in the micro-ring resonant cavity to generate a declared single-photon source. The system obtains a target pulse by superimposing a first pulse and a second pulse with a target phase difference, and then resonates the obtained target pulse in the micro-ring resonant cavity to generate a declared single-photon source, which can effectively improve the purity of the generated declared single-photon source. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0045] Figure 1 is a schematic diagram of a single photon source system provided in an embodiment of the present application;

[0046] Figure 2 is a schematic diagram of spontaneous four-wave mixing provided in an embodiment of the present application;

[0047] Figure 3 is a schematic diagram of degenerate pumping provided in an embodiment of the present application;

[0048] Figure 4 is a schematic diagram of the resonance process of the micro-ring resonant cavity provided in an embodiment of the present application;

[0049] Figure 5 Schematic diagram of the amplitude-frequency characteristics of the target pulse provided in the embodiment of the present application:

[0050] Figure 6 is a schematic diagram of the phase-frequency characteristics of the target pulse provided by an embodiment of the present application;

[0051] Figure 7 is a schematic diagram of a time domain waveform of a target pulse provided in an embodiment of the present application;

[0052] Figure 8 is a schematic diagram of a waveform shaper provided in an embodiment of the present application generating a target pulse;

[0053] Fig. 9 is a schematic diagram of AMZI generating target pulses provided in an embodiment of the present application;

[0054] Fig.10 It is a flow chart of the single photon source generation method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0056] The present application embodiment provides a single photon source system. Figure 1 , Figure 1 is a schematic diagram of a single photon source system provided in an embodiment of the present application, such as Figure 1 As shown, the single photon source system includes:

[0057] A first module, wherein the first module comprises a pulse processing unit and a micro-ring resonant cavity, wherein an output end of the pulse processing unit is connected to an input end of the micro-ring resonant cavity;

[0058] Wherein, the pulse processing unit is used to generate a first pulse and a second pulse with a target phase difference, and generate a target pulse by superimposing the first pulse and the second pulse;

[0059] The micro-ring resonant cavity is used to make the target pulse resonate in the micro-ring resonant cavity to generate a declared single photon source.

[0060] To facilitate understanding of the embodiments of the present application, the relevant technical knowledge and technical principles involved in the embodiments of the present application are described below:

[0061] See also Figure 2 , Figure 2 The process of spontaneous four-wave mixing (SFMW) promoted by the nonlinear effect of nonlinear crystals is described. As a third-order nonlinear process, SFMW contains four wave components. Figure 3 , in the degenerate pumping scheme, at ω p The two pump photons at ω s and ω i Around ω p Generate a pair of photons. An electron is excited by two pump photons to the corresponding The virtual energy level is then generated by emitting two energies and The energy and momentum of this process are conserved. In this pair of photons, one photon is called a signal photon and the other is called an idler photon. Generally, the presence of a signal photon is predicted by detecting the presence of an idler photon. Therefore, this pair of photons is usually called a heralded single photon source.

[0062] See also Figure 4 , Figure 4 The process of generating signal photons and idler photons by spontaneous four-wave mixing effect of pump light through a microring resonator is described. It should be noted that for the microring resonator of the embodiment of the present application, silicon is mainly used as the material because of its resonance enhancement effect for light that meets the resonance conditions. Even if a very weak pump photon is input, a strong nonlinear effect can still occur.

[0063] In quantum mechanics, the interaction between the pump and signal idler photon pairs can be expressed by the effective Hamiltonian H. int To describe, see expression (1):

[0064]

[0065] In expression (1), the normalization constant N is related to the strength of the interaction, and the joint spectral amplitude f(ω s ,ω i ) contains the energy and momentum of the interaction is conserved, Hc represents Hermitian conjugation, and represents the production operator that acts on the vacuum and produces signal photons and the production operator that produces idler photons.

[0066] For low-power pump photons, only a single pair of signal photons and idler photons can be probabilistically generated in the microring resonator. In the case of a pure state, the two-photon part of the output quantum state can be seen in expression (2):

[0067]

[0068] Assuming there is no spectral overlap with adjacent resonances, R can be obtained from expression (3):

[0069]

[0070] The purity of the photon pair source can be obtained by performing Schmidt decomposition on the joint spectrum amplitude, wherein the process of Schmidt decomposition of the joint spectrum amplitude can be seen in expression (4), the purity p can be seen in expression (5), and R can be seen in expression (6):

[0071]

[0072]

[0073] R=∑kλk2 (6)

[0074] Therefore, when the joint spectrum amplitude f(ωs,ωi) can be completely separated, pure idler photons will be generated, that is, P is 1, see expression (7), at this time the joint spectrum amplitude f(ωs,ωi) can be expressed as:

[0075] f(ωs,ωi)=λΨi(ωi)Ψs(ωs) (7)

[0076] In the case of spontaneous four-wave mixing of signal photons and idler photons through a microring resonator, referring to expression (8), the joint spectrum amplitude f(ωs, ωi) can be expressed as:

[0077] f(ωs,ωi)=Fp(ωs+ωi)li(ωi)ls(ωs)(8)

[0078] Among them, the pump pulse spectrum function Fp(ω) input to the microring resonator can be seen in expression (9), and the field enhancement function l of the microring resonator is j (ω j ) can be found in expression (10):

[0079] F p (ω)=∫dω′α p (ω-ω′)l p (ω-ω′)α p (ω′)l p (ω′) (9)

[0080]

[0081] The joint spectral amplitude f(ω s ,ω i ) contains only the spectrum of the pump pulse F at the input microring resonator. p (ω s +ω i ). Therefore, if the pump pulse spectrum F p (ω) and field enhancement of micro-ring resonator j (ω j ) changes slowly compared to the joint spectrum amplitude f(ω s ,ω i ) can be almost decomposed. However, the pump pulse spectrum F p (ω) is itself spectrally enhanced by the field of its corresponding microring resonator. j (ω j ) limit, prohibiting the input of Gaussian pulses with arbitrary spectral width. Therefore, consider replacing α in expression (9) with p (ω') with αp tar (ω) is substituted, α p tar (ω) For details, please refer to expression (11):

[0082] α p tar (ω) = l p -1 (ω)exp(-ω 2 / 2σ 2 ) (11)

[0083] This leads to the obtained F p (ω) compared to l j (ω j ) changes much more slowly, at this time F p (ω) can be approximately regarded as a constant, then the joint spectrum amplitude f(ω s ,ω i ) can almost be decomposed.

[0084] The pump pulse obtained after replacement is the target pulse mentioned above. The amplitude-frequency characteristics and phase-frequency characteristics of the target pulse can be found in Figure 5 and Figure 6 The time domain waveform of the target pulse can be obtained by Fourier transforming expression (11). The time domain waveform diagram can be found in Figure 7 ,pass Figure 7 It can be seen that the target pulse can be obtained by superimposing the first pulse and the second pulse with the target phase difference through the pulse processing unit. The aforementioned target phase difference can be π, see expression (12). This double pulse superposition method can be expressed as:

[0085]

[0086] In expression (12), where τ p is the pulse duration, Δτ is the time interval between pulses, and η is the relative pulse weight.

[0087] Afterwards, the obtained target pulse is resonated in the microring resonator to produce a declared single photon source.

[0088] In an embodiment of the present application, a first pulse and a second pulse having a target phase difference are superimposed through a first module to obtain a target pulse, and then the obtained target pulse is resonated in a microring resonator (MRR) to generate a heralded single photon source, which can effectively improve the purity of the generated heralded single photon source. It should be noted that the first module in the embodiment of the present application can be understood as a heralded single photon source HSPS (Heralded Single PhotonSource, HSPS) module.

[0089] Optionally, the single photon source system further comprises at least one of the following:

[0090] A separation module, a detection module, a buffer module, a driving module and an output module, wherein the input end of the separation module is connected to the output end of the microring resonant cavity, the first output end and the second output end of the separation module are respectively connected to the input end of the detection module and the input end of the buffer module, the output end of the detection module is connected to the input end of the driving module, the output end of the driving module is connected to the control end of the output module, and the output end of the buffer module is connected to the input end of the output module, wherein:

[0091] The separation module is used to separate the announced single photon source into idler photons and signal photons, and output them through the first output end and the second output end of the separation module respectively;

[0092] The detection module is used for sending a first electrical signal to the driving module when the idler photon is detected;

[0093] The buffer module is used to buffer the signal photons;

[0094] The driving module is used to drive the optical switch when receiving the first electrical signal;

[0095] The output module is used to output the signal photons under the drive of the driving module.

[0096] In one embodiment, continue to refer to Figure 1, the single photon source system also includes a separation module, a detection module, a buffer module, a driving module and an output module. The separation module can be an arrayed waveguide grating (AWG), the detection module can be a single photon detector (SPD), the buffer module can be an optical delay line (ODL), the driving module can be a field programmable gate array (FPGA), and the output module can be an optical switch. It should be noted that the separation module, detection module, buffer module, driving module and output module mentioned in the embodiment of the present application are not limited to the aforementioned devices, and can also be other devices that play the same role. The input end of the separation module is connected to the output end of the micro-ring resonant cavity, and the micro-ring resonant cavity inputs the generated announcement single photon source into the separation module, and the separation module separates the announcement single photon source into idler light and signal light. The first output end of the separation module is connected to the input end of the detection module, and the idler light is output through the first output end of the separation module and then input into the detection module. The second output end of the separation module is connected to the input end of the buffer module, and the signal photon is output through the second output end of the separation module and then input to the buffer module for buffering.

[0097] The output end of the detection module is connected to the input end of the driving module. When the detection module detects idle photons, the first electrical signal is sent to the driving module. The output end of the driving module is connected to the control end of the output module, and the output end of the buffer module is connected to the input end of the output module. When the driving module receives the first electrical signal, it drives the output module to output the signal photons in the buffer module.

[0098] In this implementation, the presence of idle photons is accurately detected by the detection module, and the signal photons are output by the logic control of the output module by the driving module.

[0099] Optionally, the single photon source system further comprises:

[0100] Laser and beam splitter, where

[0101] The laser is used to generate a third pump pulse;

[0102] The beam splitter is used to split a beam of the third pump pulse into N fourth pump pulses, where N is an integer greater than 1;

[0103] The single-photon source system includes N first modules, and each fourth pump pulse is input into one first module respectively; a pulse processing unit is used to convert one fourth pump pulse into the first pulse and the second pulse.

[0104] In one embodiment, the single-photon source system further includes a laser and a beam splitter. The beam splitter may be a spectroscope, a coupler, and an interference beam splitter. The laser generates a third pump pulse, and the beam splitter divides a beam of the third pump pulse into N fourth pump pulses. It should be noted that the aforementioned third and fourth are only for distinction. In essence, the third pump pulse and the fourth pump pulse only differ in power, and there is no difference in other properties. Each pump pulse corresponds to an input of a first module, and the manner in which each first module generates a declared single-photon source may be the same or similar. The specific generation method may refer to the relevant introduction in the aforementioned embodiment.

[0105] In this embodiment, see Figure 1 , a beam of third pump pulses is divided into N fourth pump pulses, each of which is subsequently processed through the first module, the separation module, the detection module and the buffer module, and the output end of each detection module is connected to the input end of the driving module, which is conducive to increasing the probability of detecting signal photons in the announcement-type single-photon source through multiplexing, outputting signal photons, and thus improving the brightness of the announcement-type single-photon source.

[0106] Optionally, the single photon source system comprises a first port and a second port, wherein:

[0107] The first port is used to output a target signal photon, wherein the target signal photon is a signal photon in a first announced single-photon source, and the first announced single-photon source is one of at least one announced single-photon source generated by N first modules;

[0108] The second port is used to output other photons in the at least one announced single-photon source except the target signal photon.

[0109] In one embodiment, the single-photon source system includes a first port and a second port. Specifically, when the single-photon source system includes an optical switch, the first port and the second port are arranged on the optical switch. Exemplarily, a beam of pump pulses is divided into three fourth pump pulses, and each fourth pump pulse generates a declared single-photon source based on a first module, so the three fourth pump pulses obtain a total of three declared single-photon sources. After the output light of each declared single-photon source is separated by the AWG, if the SPD of each channel detects idler photons, it indicates that signal photons are generated in each channel. However, it should be noted that the first port can only output one of the signal photons, and the other photons are output by the second port.

[0110] In this implementation, since the process of generating correlated photon pairs is random and is also affected by the detection efficiency and dark count of the single-photon detector, in practice not every announced single-photon source can detect idler photons. The probability of generating signal photons is increased by multiplexing, thereby increasing the brightness of the single-photon source. This scheme uses the physical basis of "probabilistic output of correlated photon pairs in spontaneous nonlinear optical processes" and uses a single-photon detector to detect one of the photons to obtain a forecast electrical signal to announce the output of the single photon, thereby greatly reducing the situation of "empty pulses".

[0111] Optionally, the pulse processing unit is a waveform shaper;

[0112] The waveform shaper is used for converting the input fourth pump pulse into the first pulse and the second pulse having the target phase difference, and obtaining the target pulse by adjusting the waveforms of the first pulse and the second pulse.

[0113] In one embodiment, the pulse processing unit is a waveform shaper (Wave Shaper), see Figure 8 , the fourth pump pulse is input into the Wave Shaper to be converted into the first pulse and the second pulse with the target phase difference, and then the target pulse is obtained by adjusting the waveforms of the first pulse and the second pulse, and then the target pulse is input into the MRR, which is conducive to obtaining a high-purity announced single photon source. The aforementioned waveform shaper can be a chirped grating, an intensity modulator, etc.

[0114] Optionally, the pulse processing unit is an unequal-arm Mach-Zehnder interferometer AMZI;

[0115] The AMZI is used to divide the input fourth pump pulse into two pump pulses, and obtain the first pulse and the second pulse by controlling the relative phase difference and relative intensity of the two pump pulses; and generate the target pulse by superimposing the first pulse and the second pulse.

[0116] In one embodiment, the pulse processing unit is an unequal-arm Mach-Zehnder Interferometer (AMZI), see Fig. 9, input the fourth pump pulse into AMZI, and obtain two pump pulses with a power ratio of 50:50 through the beam splitter, and then add a phase controller (PM) on the two arms of AMZI to control the relative phase difference of the two pump pulses, and control the relative intensity of the two pump pulses through the polarization controller (PC) on the two arms of AMZI to obtain the first pulse and the second pulse, and then superimpose the first pulse and the second pulse through the beam splitter to generate the target pulse, and then pass through the polarizing beam splitter (PBS), and then input the target pulse into the MRR, which is conducive to obtaining a high-purity declared single-photon source.

[0117] The present application also provides a method for generating a single photon source. Fig.10 , Fig.10 Flow chart of a single photon source generation method, the single photon source generation method comprising:

[0118] Step 1001, generating a first pulse and a second pulse with a target phase difference, and generating a target pulse by superimposing the first pulse and the second pulse;

[0119] Step 1002: Generate a propagation-type single-photon source by causing the target pulse to resonate.

[0120] Optionally, after causing the target pulse to resonate and generate a declared single photon source, the method further comprises:

[0121] Separating the announced single photon source into idler photons and signal photons, wherein the idler photons enter the detection module and the signal photons enter the buffer module;

[0122] When the idler photon is detected, the signal photon is output.

[0123] Optionally, before generating the first pulse and the second pulse with a target phase difference and generating the target pulse by superimposing the first pulse and the second pulse, the method further includes:

[0124] dividing a beam of third pump pulses into N fourth pump pulses, where N is an integer greater than 1;

[0125] Respectively converting each of the fourth pump pulses into the first pulse and the second pulse to obtain N channels of the first pulse and the second pulse;

[0126] Generating a target pulse by superimposing the first pulse and the second pulse comprises:

[0127] Generate a target pulse by superimposing each of the first pulse and the second pulse to obtain N target pulses;

[0128] The method of generating a single photon source by resonating the target pulse comprises:

[0129] By resonating each of the target pulses, respectively, at least one declared single photon source is generated.

[0130] It should be noted that this embodiment is Figure 1 The corresponding method implementation in the embodiment shown in the figure can be found in the specific implementation Figure 1 The relevant description of the embodiment shown in the figure can achieve the same Figure 1 The same technical effects as those of the embodiments shown are not described in detail in this embodiment to avoid repeated description.

[0131] The present application also provides an optical device, which includes the single photon source system as described above. Figure 1 The same technical effects as those of the embodiments shown are not described in detail in this embodiment to avoid repeated description.

[0132] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0133] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0134] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A single photon source system, characterized in that: The single photon source system comprises: A first module, wherein the first module comprises a pulse processing unit and a micro-ring resonant cavity, wherein an output end of the pulse processing unit is connected to an input end of the micro-ring resonant cavity; Wherein, the pulse processing unit is used to generate a first pulse and a second pulse with a target phase difference, and generate a target pulse by superimposing the first pulse and the second pulse; The micro-ring resonant cavity is used to make the target pulse resonate in the micro-ring resonant cavity to generate a declared single photon source.

2. The single photon source system according to claim 1, characterized in that: The single photon source system further comprises at least one of the following: A separation module, a detection module, a buffer module, a driving module and an output module, wherein the input end of the separation module is connected to the output end of the microring resonant cavity, the first output end and the second output end of the separation module are respectively connected to the input end of the detection module and the input end of the buffer module, the output end of the detection module is connected to the input end of the driving module, the output end of the driving module is connected to the control end of the output module, and the output end of the buffer module is connected to the input end of the output module, wherein: The separation module is used to separate the announced single photon source into idler photons and signal photons, and output them through the first output end and the second output end of the separation module respectively; The detection module is used for sending a first electrical signal to the driving module when the idler photon is detected; The buffer module is used to buffer the signal photons; The driving module is used to drive the optical switch when receiving the first electrical signal; The output module is used to output the signal photons under the drive of the driving module.

3. The single photon source system according to claim 1 or 2, characterized in that: The single photon source system further comprises: Laser and beam splitter, where The laser is used to generate a third pump pulse; The beam splitter is used to split a beam of the third pump pulse into N fourth pump pulses, where N is an integer greater than 1; The single-photon source system includes N first modules, and each fourth pump pulse is input into one first module respectively; a pulse processing unit is used to convert one fourth pump pulse into the first pulse and the second pulse.

4. The single photon source system according to claim 3, characterized in that: The single photon source system comprises a first port and a second port, wherein: The first port is used to output a target signal photon, wherein the target signal photon is a signal photon in a first announced single-photon source, and the first announced single-photon source is one of at least one announced single-photon source generated by N first modules; The second port is used to output other photons in the at least one announced single-photon source except the target signal photon.

5. The single photon source system according to claim 1 or 2, characterized in that: The pulse processing unit is a waveform shaper; The waveform shaper is used for converting the input fourth pump pulse into the first pulse and the second pulse having the target phase difference, and obtaining the target pulse by adjusting the waveforms of the first pulse and the second pulse.

6. The single photon source system according to claim 1 or 2, characterized in that: The pulse processing unit is an unequal-arm Mach-Zehnder interferometer AMZI; The AMZI is used to divide the input fourth pump pulse into two pump pulses, and obtain the first pulse and the second pulse by controlling the relative phase difference and relative intensity of the two pump pulses; and generate the target pulse by superimposing the first pulse and the second pulse.

7. A method for generating a single photon source, characterized in that: The single photon source system used in any one of claims 1 to 6, comprising: Generate a first pulse and a second pulse with a target phase difference, and generate a target pulse by superimposing the first pulse and the second pulse; By resonating the target pulse, a propagation-type single photon source is generated.

8. The single photon source generation method according to claim 7, characterized in that: After causing the target pulse to resonate and generate a declared single photon source, the method further includes: Separating the announced single photon source into idler photons and signal photons, wherein the idler photons enter the detection module and the signal photons enter the buffer module; When the idler photon is detected, the signal photon is output.

9. The single photon source generation method according to claim 7 or 8, characterized in that: Before generating the first pulse and the second pulse with a target phase difference, and generating the target pulse by superimposing the first pulse and the second pulse, the method further includes: dividing a beam of third pump pulses into N fourth pump pulses, where N is an integer greater than 1; Respectively converting each of the fourth pump pulses into the first pulse and the second pulse to obtain N channels of the first pulse and the second pulse; Generating a target pulse by superimposing the first pulse and the second pulse comprises: Generate a target pulse by superimposing each of the first pulse and the second pulse to obtain N target pulses; The method of generating a single photon source by resonating the target pulse comprises: By resonating each of the target pulses, respectively, at least one declared single photon source is generated.

10. An optical device, characterized in that: The optical device comprises the single photon source system according to any one of claims 1-6.

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