A spatiotemporal multiplexed optical quantum interference device

Abstract

The utility model provides a kind of light quantum interference device of air reuse, comprising: N+1 stage interference components, each stage interference component is suitable for receiving M beam parametric light, parametric light is pulse light, each parametric light includes multiple light pulses transmitted in time sequence, each stage interference component is also suitable for making the interference of M light pulses received at the same time, obtains M beam interference light;N stage optical fiber delay array, wherein, the i stage optical fiber delay array in N stage optical fiber delay array is arranged between i stage interference component and i+1 stage interference component, each stage optical fiber delay array includes M delay ring, M delay ring one-to-one corresponding to the delay of received M beam interference light, the time delay amount of M delay ring is different;Wherein, the M beam delayed interference light output by i stage optical fiber delay array is as input to M beam parametric light of i+1 stage interference component, 1≤i≤N, M>1.

Description

Technical Field

[0001] At least one embodiment of this utility model relates to the field of quantum information technology, and more specifically, to a spatiotemporal multiplexing optical quantum interference device. Background Technology

[0002] Interferometers for photons are primarily used to achieve interference between input photon signals of different modes. For example, a Mach-Zehnder or Sagnac interferometer with a single-mode input photon signal can achieve single-photon interference, while a Hong-Ou-Mandel interferometer with two modes of input single-photon signals can achieve interference between two identical photons. Scalable multimode interferometers can perform linear transformations of the input photon state, playing a crucial role in quantum computing, optical networks, and precision quantum measurement.

[0003] In related technologies, it has been demonstrated that arbitrary unitary transformations of the input quantum state can be achieved using 2×2 beam splitters and phase plates as basic components. For example, a two-mode Mach-Zehnder interferometer constructed using two beam splitters with a 50:50 splitting ratio and a phase plate is equivalent to a beam splitter with an arbitrary splitting ratio. By using multiple such cascaded Mach-Zehnder interferometers, an interferometer with multiple modes can be constructed.

[0004] There are currently two main technical approaches for large-scale, multi-mode photonic interferometry networks. One is spatially encoded interferometers, which have the advantages of high connectivity and low photon loss, but the disadvantages of low scalability and high cost of increasing the number of modes. The other approach is time-coded interferometer structures, which have the advantage of extremely high scalability, but the disadvantages of low connectivity and exponential decay of system efficiency with the number of interferometer layers. Utility Model Content

[0005] In view of this, the present invention provides a spatiotemporal multiplexing optical quantum interference device.

[0006] As one aspect of this utility model, a spatiotemporal multiplexing optical quantum interference device is provided, comprising:

[0007] The N+1 stage interference components are each suitable for receiving M beams of parametric light, wherein the parametric light is pulsed light, each parametric light includes multiple light pulses transmitted in a time sequence, and each stage interference component is also suitable for causing the M light pulses received at the same time to interfere, thereby obtaining M beams of interference light.

[0008] The N-level fiber delay array is configured such that the i-th level fiber delay array is positioned between the i-th level interference component and the (i+1)-th level interference component. Each level fiber delay array includes M delay loops, which delay the received M beams of interference light in a one-to-one correspondence. The delay amounts of the M delay loops are different.

[0009] Among them, the M delayed interference beams output by the i-th stage fiber delay array are used as the M parametric beams input to the (i+1)-th stage interference component, where 1≤i≤N and M>1.

[0010] According to an embodiment of the present invention, the optical quantum interference device further includes:

[0011] N+1 level output components, wherein the i-th level output component in the N+1 level output components is suitable for receiving M beams of interference light output by the i-th level interference component, 1≤i≤N;

[0012] Each level of output components includes:

[0013] Adjust the platform;

[0014] Multiple reflection modules are located on the adjustment platform and are suitable for reflecting the received M-beam interference light;

[0015] The adjustment platform is suitable for adjusting the pose of multiple reflection modules to change the spacing of the M-beam interference beams; the M-beam interference beams output by the i-th stage output component are transmitted to the i-th stage fiber delay array.

[0016] According to an embodiment of the present invention, the optical quantum interference device further includes:

[0017] There are N+1 beam-splitting components, wherein the i-th beam-splitting component is adapted to reflect the M-beam interference light output by the i-th stage interference component to the i-th stage output component, and the N+1-th stage beam-splitting component is adapted to reflect the M-beam interference light output by the N+1-th stage interference component to the N+1-th stage output component.

[0018] According to an embodiment of the present invention, the optical quantum interference device further includes:

[0019] Light source components suitable for generating pump light:

[0020] A beam splitter assembly suitable for splitting the pump light into M sub-pump lights;

[0021] M optical parametric resonant cavities are used to perform downparametric conversion on a portion of each of the M sub-pump beams to obtain the M beams of parametric light;

[0022] After the lower parameter conversion is completed, the remaining sub-pump light also includes M beams, and the remaining m-th sub-pump light and the m-th pulse light are output through the same optical path.

[0023] According to an embodiment of the present invention, the above-mentioned optical quantum interference device further includes:

[0024] Pre-locked loop assembly, including:

[0025] There are M control modules, of which the m-th control module is suitable for receiving the m-th sub-pump light;

[0026] A dichroic mirror is used to separate the remaining sub-pump light and the parametric light of the M-beam; and to transmit the parametric light of the M-beam to the first-stage interference component;

[0027] The beam splitting unit is suitable for splitting external reference pump light into M beams;

[0028] The beam combining unit is suitable for combining M remaining sub-pump beams and M reference pump beams to obtain M first combined beams, wherein the m remaining sub-pump beam and the m reference pump beam are combined to obtain the m first combined beam.

[0029] M fiber polarization beam splitters, wherein the m-th fiber polarization beam splitter among the M fiber polarization beam splitters is suitable for splitting the m-th first combined beam into two sub-combined beams.

[0030] M photoelectric detection units, wherein the m-th photoelectric detection unit is adapted to detect the two sub-beams split from the m-th first combined beam, and emits the m-th driving signal according to the detection results of each. The m-th driving signal is adapted to drive the m-th control module to adjust the optical path of the m-th sub-pump beam, thereby realizing the adjustment of the phase of the m-th parametric beam.

[0031] According to an embodiment of the present invention, the M-beam phase-locked light from the (i+1)th stage interference component is reflected by the i-th stage output component and then passes through the i-th beam splitter component;

[0032] Between the (i+1)th level interference component and the i-th beam splitter component, the m-th phase-locked beam and the m-th interference beam are transmitted along the same optical path;

[0033] The optical quantum interference device further includes N phase-locked loop components, wherein the i-th phase-locked loop component includes:

[0034] The beam splitting module is suitable for splitting incident light from the outside into M reference beams;

[0035] A beam combining module is suitable for combining M beams of reference light and M beams of phase-locked light passing through the i-th beam splitter to obtain the M-th second beam combining light, wherein the m-th beam of reference light and the m-th beam of phase-locked light passing through the i-th beam splitter are combined to obtain the m-th second beam combining light.

[0036] Transmission module, suitable for transmitting M second-beam combined optical signals;

[0037] The adjustment module is adapted to adjust the optical path of the m-th parametric light incident on the (i+1)-th interference component according to the optical power of the m-th second combined beam, thereby fixing the phase of the m-th parametric light incident on the (i+1)-th interference component, where m≤M.

[0038] According to an embodiment of the present invention, each stage of the fiber delay array further includes a temperature control component, which is suitable for maintaining the length of the M delay loops unchanged.

[0039] According to an embodiment of the present invention, each output component further includes an output collimator group; the output collimator group includes M output collimators, and the M output collimators of the i-th output collimator group are adapted to collimate the M beams of interference light output by the i-th output component and transmit the collimated M beams of interference light to the M delay loops of the i-th stage fiber delay array.

[0040] According to an embodiment of the present invention, the optical quantum interference device further includes:

[0041] The N-level input component, wherein the i-th level input component is connected to the i-th level fiber delay array and is adapted to input the M-beams of delayed interference light output from the i-th level fiber delay array to the (i+1)-th level interference component.

[0042] According to embodiments of this utility model, through the cascaded design of N+1 level interference components and N level fiber delay arrays, combined with the structure that each level interference component processes M beams of parametric light and each parametric light contains multiple time-series optical pulses, the composite multiplexing of spatial and temporal modes can be realized. This enables a large number of optical pulses to achieve fully connected interference in the spatiotemporal dimension, expands the scale of optical quantum interference, and provides a hardware foundation for applications such as large-scale optical quantum computing and high-precision optical quantum precision measurement.

[0043] According to embodiments of this invention, each stage of the fiber delay array has M delay rings with different time delays, which can precisely control the time delay of optical pulses, ensuring that optical pulses arriving at the interference component at the same time participate in the interference and guaranteeing the time synchronization of the interference. Simultaneously, this hierarchical delay and interference structure, combined with subsequent possible phase-locked loop systems, can effectively suppress the influence of environmental factors (such as temperature and vibration) on the optical path and phase, improving the accuracy and stability of the entire interference system and making the interference results more reliable. Attached Figure Description

[0044] The above and other objects, features and advantages of the present invention will become clearer from the following description of embodiments of the present invention with reference to the accompanying drawings, in which:

[0045] Figure 1 A structural diagram of a spatiotemporal multiplexing optical quantum interference device according to an embodiment of the present invention is shown.

[0046] Figure 2 The present invention provides an embodiment of the present invention. Figure 1 A schematic diagram of the optical quantum interference device.

[0047] Figure 3 A schematic diagram illustrating the principle of phase locking of parametric light according to an embodiment of the present invention is shown.

[0048] Figure 4 An optical path diagram of any output component provided according to an embodiment of the present invention is shown.

[0049] Figure 5 An optical path diagram of the first-stage output component provided according to an embodiment of the present invention is shown.

[0050] Figure 6 An optical path diagram of a second-stage output component or a third-stage output component provided according to an embodiment of the present invention is shown.

[0051] Figure 7 A partial structural diagram of the first phase-locked assembly provided according to an embodiment of the present invention is shown.

[0052] Figure 8 A schematic diagram of another part of the structure of the first phase-locked assembly provided according to an embodiment of the present invention is shown.

[0053] Figure 9 A schematic diagram of a triangular interference module provided according to an embodiment of the present invention is shown.

[0054] Figure 10 A schematic diagram illustrating the programmability of the interference device provided according to an embodiment of the present invention is shown.

[0055] Figure 11 A schematic diagram illustrating the principle and implementation of internal phase calibration of the interference component provided in this embodiment of the utility model.

[0056] Explanation of reference numerals in the attached figures:

[0057] 11: First-stage interference component; 12: Second-stage interference component; 13: Third-stage interference component; 14: Pre-locked loop component; 14-1: Control module; 14-2: Dichroic mirror; 14-3: Second beam splitter unit; 14-4: Beam combiner unit; 14-5: Fiber polarization beam splitter; 14-6: Photoelectric detection unit; 21: First-stage fiber delay array; 22: Second-stage fiber delay array; 31: First-stage output component; 32: Second-stage output component; 33: Third-stage output component; 41: Adjustment platform; 42: Second mirror array; 43: Output collimator group; 44: Second waveplate group array; 45: First planar circular mirror array; 52: Beam splitting component; 521: First half-wave plate; 522: First polarization beam splitting unit; 53: Optical parametric resonator cavity; 61: First-stage input component; 62: Second-stage input component; 71: TEC temperature-controlled collimator array; 72: First waveplate group array; 73: First mirror array; 74: Second planar circular mirror array; 81: First beam splitting component; 82: Second beam splitting component; 83: Third beam splitting component; 101: First phase-locked module; 102: Second phase-locked module; 111: Beam splitting module; 112 113 Beam combining module; 114-1 Transmission module; 114-2 First phototube; 114-3 Second half-wave plate; 114-4 Second polarization beam splitting unit; 114-5 Modulation unit; 114-6 Collimator; 114-7 Phase-locked optical control unit; 121 Vibration isolation plate; 122 Water-cooled circulating temperature control plate; 123 Ultra-low expansion glass; 124 Fused silica support; 125 First triangular interferometer; 126 Square mirror; 127 Second triangular interferometer; 131 Laser; 132 First acousto-optic modulator; 133 Second acousto-optic modulator; 134 Third acousto-optic modulator; 135 Fourth acousto-optic modulator; 136 Fifth acousto-optic modulator; 137 Third half-wave plate; 138 Second mirror; 139 Mechanical optical switch; 140 Interference assembly; 141 Analog-to-digital converter; 142 Second phototube. Detailed Implementation

[0058] The embodiments of the present invention will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, numerous specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the present invention.

[0059] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0060] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0061] Figure 1 A structural diagram of a spatiotemporal multiplexing optical quantum interference device according to an embodiment of the present invention is shown.

[0062] like Figure 1 As shown, the optical quantum interference device includes: an N+1 level interference component and an N-level fiber delay array. Figure 1 The example provided is a three-stage interference assembly (i.e., N=2) and a two-stage fiber delay array. Figure 1 The three levels of interferometry components are level 1 interferometry component 11, level 2 interferometry component 12, and level 3 interferometry component 13. Figure 1 In the middle, the two-stage fiber delay arrays are the first-stage fiber delay array 21 and the second-stage fiber delay array 22.

[0063] Each stage of the interferometer is suitable for receiving M beams of parametric light, which are pulsed beams. Each parametric light consists of multiple optical pulses transmitted in a time sequence. Each stage of the interferometer is also suitable for interfering the M optical pulses received at the same time, resulting in M ​​beams of interference light. The i-th stage of the N-stage fiber delay array is positioned between the i-th stage and the (i+1)-th stage interferometer. Each stage of the fiber delay array includes M delay loops, each delaying the received M beams of interference light in a one-to-one correspondence. The delay amounts of the M delay loops are different. The M delayed beams of interference light output from the i-th stage fiber delay array are used as the input M beams of parametric light to the (i+1)-th stage interferometer, where 1 ≤ i ≤ N, M > 1. The M beams of parametric light are beams with a Gaussian mode.

[0064] Combination Figure 1 A first-stage fiber delay array 21 is provided between the first-stage interference component 11 and the second-stage interference component 12, and a second-stage fiber delay array 22 is provided between the second-stage interference component 12 and the third-stage interference component 13.

[0065] According to the embodiments of this utility model, the spatiotemporal multiplexing optical quantum interference device, through the cascaded design of N+1 level interference components and N level fiber delay arrays, combined with the structure that each level interference component processes M beams of parametric light and each parametric light contains multiple time-series optical pulses, can realize the composite multiplexing of spatial and temporal modes, enabling a large number of optical pulses to achieve fully connected interference in the spatiotemporal dimension, expanding the scale of optical quantum interference, and providing a hardware foundation for applications such as large-scale optical quantum computing and high-precision optical quantum precision measurement.

[0066] According to embodiments of this invention, each stage of the fiber delay array has M delay rings with different time delays, which can precisely control the time delay of optical pulses, ensuring that optical pulses arriving at the interference component at the same time participate in the interference and guaranteeing the time synchronization of the interference. Simultaneously, this hierarchical delay and interference structure, combined with subsequent possible phase-locked loop systems, can effectively suppress the influence of environmental factors (such as temperature and vibration) on the optical path and phase, improving the accuracy and stability of the entire interference system and making the interference results more reliable.

[0067] According to the embodiments of this utility model, the optical quantum interference device adopts a hierarchical interference component and an optical fiber delay array structure. Parameters such as N and M can be adjusted according to actual needs, which can flexibly adapt to optical quantum experimental scenarios of different scales. Whether it is a small-scale optical quantum interference verification experiment or a large-scale optical quantum computing system, the requirements can be met by adjusting the number of stages and the number of beams processed per stage, which has strong scalability and versatility.

[0068] Figure 2 The present invention provides an embodiment of the present invention. Figure 1 A schematic diagram of the optical quantum interference device.

[0069] like Figure 2 As shown, the example still includes a 3-stage interference component (i.e., N=2) and a 2-stage fiber delay array.

[0070] Three levels of interferometers (level 1 interferometer 11 to level 3 interferometer 13) are arranged longitudinally. Each level of interferometer can receive M beams of parametric light (containing multiple time-sequential light pulses) and allow the M light pulses arriving at the same time to complete fully connected interference in the spatial dimension within the interferometer, outputting M beams of interference light. Two levels of fiber delay arrays are sandwiched between adjacent interferometers. Each level of fiber delay array contains M delay loops that correspond one-to-one with the interference light. Using τ (the time it takes for light to travel through a standard-length fiber) as the basic delay unit, the M delay loops of the level 1 fiber delay array are set with differentiated delays of 1τ...Mτ, allowing the interference light to form multiple time patterns before being transmitted to the level 2 interferometer. The M delay loops of the level 2 fiber delay array are set with delays of Mτ, 2Mτ...Mτ, respectively. 2The differentiated time delay of τ allows the interferometric light to form multiple time patterns, which are then transmitted to the third-stage interferometer. The aforementioned interferometer device diffuses one time pattern to subsequent stages. In terms of temporal modes, it achieves extreme time connectivity. The final stage of the interferometer diffuses the temporally dense, spatially sparse pulse array from the previous stage onto all spatial modes. The entire interferometer device completes the spatiotemporal composite interference of photons through a cascaded process of spatial interference from the interferometer components and temporal delay from the fiber delay array, meeting the requirements of large-scale quantum operations.

[0071] According to an embodiment of this utility model, before interfering with the M-beam parametric beams, it is necessary to lock the phase of the M-beam parametric beams to ensure the smooth completion of the interference process. The following is a description of... Figure 3 The principle of parametric phase locking is explained in detail.

[0072] Figure 3 A schematic diagram illustrating the principle of phase locking of parametric light according to an embodiment of the present invention is shown.

[0073] like Figure 3 As shown, the aforementioned optical quantum interference device further includes: a light source assembly, a beam splitter assembly 52, and M optical parametric resonators 53. The light source assembly is suitable for generating pump light, the wavelength of which can be, for example, 775 nm. The beam splitter assembly 52 is suitable for splitting the pump light into M sub-pump beams. The beam splitter assembly 52 may include a first half-wave plate 521 and a plurality of first polarization beam splitters 522. The first half-wave plate 521 is used to change the polarization direction of the pump light, and the plurality of first polarization beam splitters 522 ( Figure 3 Only one is shown in the diagram) for splitting the pump light into M sub-pump beams. M optical parametric resonators 53 are adapted to perform downparametric conversion on a portion of each of the M sub-pump beams to obtain M beams of parametric light. Each optical parametric resonator 53 is adapted to perform downparametric conversion on a received sub-pump beam. After the downparametric conversion of the M sub-pump beams is completed, the remaining sub-pump beams also include M beams (each sub-pump beam becomes a remaining sub-pump beam), and the m-th remaining sub-pump beam and the m-th pulse beam are output along the same optical path.

[0074] According to an embodiment of this invention, the core function of the light source component is to generate pump light (typically a high-power, high-coherence laser) for exciting quantum effects. After receiving the pump light, the beam-splitting component 52 uniformly divides it into M independent sub-pump lights using optical beam-splitting principles (such as a beam splitter array). Each sub-pump light corresponds to a subsequent optical parametric resonator, providing an energy source for the parallel generation of the M parametric lights. Within each optical parametric resonator 53, a portion of the energy of the sub-pump light is converted into parametric light through a quantum optical process called downparametric conversion. The M independent parametric lights ultimately formed by the M optical parametric resonators 53 are the core working light for the subsequent spatiotemporal multiplexing interference of the interference component. During the downparametric conversion process, each sub-pump light is not completely consumed; a portion that does not participate in the downconversion remains (i.e., the remaining sub-pump light). In this embodiment, the m-th remaining sub-pump light (corresponding to the m-th optical parametric resonator) is transmitted and output along the same optical path as the m-th parametric light. Here, "common path" means that the two share the same transmission path in space (like a single optical fiber or a set of lenses), but can be distinguished by characteristics such as wavelength, and do not interfere with each other.

[0075] refer to Figure 1 and Figure 3 According to an embodiment of this utility model, the above-mentioned optical quantum interference device further includes: a pre-phase-locked module 14. This module includes: M control modules 14-1 ( Figure 3 Only one is shown in the diagram, namely the m-th control module 14-1 mentioned later. Control module 14-1 can be, for example, a piezoelectric ceramic, a dichroic mirror 14-2, a second beam splitting unit 14-3 (for example, a beam splitter), a beam combining unit 14-4 (for example, a polarization beam splitter), and M fiber polarization beam splitters 14-5. Figure 2Only one is shown in the diagram, namely the m-th fiber polarization beam splitter mentioned later. The m-th control module 111 of the M control modules is used to receive the m-th sub-pump light. The dichroic mirror 14-2 is used to separate the remaining M sub-pump lights and the M parametric lights, and transmit the M parametric lights to the first-stage interference component 11. The second beam splitting unit 14-3 is used to split the external reference pump light (wavelength 775nm) into M beams. The beam combining unit 14-4 is used to combine the remaining M sub-pump lights and the M reference sub-pump lights to obtain M first combined beams, wherein the remaining m-th sub-pump light and the m-th reference sub-pump light are combined to obtain the m-th first combined beam. The m-th fiber polarization beam splitter 14-5 in the M fiber polarization beam splitters 14-5 is used to split the m-th first combined beam into two sub-combined beams. The m-th photoelectric detection unit 146 in the M photoelectric detection units 14-6 is used to detect the two combined beams split from the m-th first combined beam and to emit the m-th driving signal according to their respective detection results. The m-th driving signal is used to drive the m-th control module 14-1 to adjust the optical path of the m-th sub-pump beam, thereby realizing the adjustment of the phase of the m-th parametric beam.

[0076] According to an embodiment of this utility model, the above-mentioned optical quantum interference device further includes: an N-stage input component, wherein the i-th stage input component is connected to the i-th stage fiber delay array, and is suitable for inputting the M-beams of delayed interference light output from the i-th stage fiber delay array to the (i+1)-th stage interference component. Figure 2 As shown, when N=2, the N-level input components are the first-level input component 61 and the second-level input component 62.

[0077] Figure 4 An optical path diagram of any output component provided according to an embodiment of the present invention is shown.

[0078] refer to Figure 1 and Figure 4Each input component includes a TEC temperature-controlled collimator array 71, a first waveplate array 72, a first mirror array 73, and a planar circular mirror array 74. Each TEC temperature-controlled collimator array 71 includes M TEC temperature-controlled collimators. The first waveplate array 72 includes M first waveplate groups. The first mirror array 73 includes multiple first right-angle mirrors. The first planar circular mirror array 74 includes M planar circular mirrors. Each of the M TEC temperature-controlled collimators collimates the received delayed interference light (i.e., parametric light). The M first waveplate groups are used to adjust the polarization reversal of the parametric light from the M TEC temperature-controlled collimators to match the subsequent interference components. The multiple first right-angle mirrors adjust the spacing between the M beams of parametric light from the M first waveplate groups. The M planar circular mirrors are used to change the transmission direction of the M beams of parametric light from the M first waveplate groups, reflecting them to the subsequent interference components. The first waveplate group consists of a quarter-wave plate and a half-wave plate.

[0079] According to an embodiment of the present invention, the above-mentioned optical quantum interference device further includes: an N+1-stage output component, wherein the i-th stage output component in the N+1-stage output component is adapted to receive M beams of interference light output by the i-th stage interference component, where 1≤i≤N.

[0080] Continue to refer to Figure 1 , Figure 1 The example provided is a three-level output component. Figure 1 The three output components are the first-level output component 31, the second-level output component 32, and the third-level output component 33.

[0081] Figure 5 An optical path diagram of the first-stage output component provided according to an embodiment of the present invention is shown.

[0082] Figure 6 An optical path diagram of a second-stage output component or a third-stage output component provided according to an embodiment of the present invention is shown.

[0083] like Figures 5-6 As shown, each stage output component includes an adjustment platform 41 and multiple second mirror arrays 42. The second mirror arrays 42 are located on the adjustment platform 41 and are used to reflect the received M-beam interference light. The second mirror arrays 42 include multiple adjustment platforms 41 suitable for adjusting the pose of the multiple second right-angle mirrors to change the spacing of the M-beam interference light; the M-beam interference light output by the i-th stage output component is transmitted to the i-th stage fiber delay array. The second mirror arrays 42 may, for example, include multiple second right-angle mirrors.

[0084] According to an embodiment of this invention, the adjustment platform 41 of each output component can adjust the orientation of multiple second right-angle mirrors, thereby changing the spacing of the M interference beams. This ensures that the beam spacing entering the next stage fiber delay array matches the interface of the delay array, making the optical path of each beam precisely controllable during transmission in the delay loop, ensuring the synchronization of different beams in the time dimension, and providing a prerequisite for the precise interference of optical pulses in subsequent interference components. By adjusting the orientation of the second right-angle mirrors through the adjustment platform 41, different specifications of fiber delay arrays and interference components can be flexibly adapted, ensuring precise optical path alignment even when parameters such as M and N are adjusted, making the entire device adaptable to different application scenarios. The reasonable layout and orientation adjustment of multiple second right-angle mirrors can optimize the beam transmission path, reduce errors such as deflection and scattering during optical path transmission, further improve the accuracy of quantum interference, and ensure the stability of the overall performance of the device.

[0085] According to an embodiment of this utility model, each output component further includes an output collimator group 43. The output collimator group 43 includes M output collimators, which are used to collimate the M beams of interference light output from the second mirror array 42. The output collimator group 43 of the i-th stage output component is used to transmit the collimated M beams of interference light to the M delay loops of the i-th stage fiber delay array. The output collimator group 43 of the N+1-th stage output component is not connected to any delay loops. Figure 2 The output collimator group 43 of the first-stage output component and the second-stage output component are both connected to delay loops, while the third-stage output component is not connected to any delay loop.

[0086] According to an embodiment of the present invention, referring to Figure 6 When i>1, each output component also includes a second waveplate array 44, which includes M second waveplate groups for adjusting the polarization of the beam between the second mirror array 42 and the output collimator group 43.

[0087] According to an embodiment of the present invention, the above-mentioned optical quantum interference device further includes: N+1 beam-splitting components, wherein the i-th beam-splitting component is adapted to reflect the M-beam interference light output from the i-th stage interference component to the i-th stage output component, and the N+1-th stage beam-splitting component is adapted to reflect the M-beam interference light output from the N+1-th stage interference component to the N+1-th stage output component. (Continue to refer to...) Figure 1 , Figure 1 The diagram shows the case with 3 beam splitters, i.e., N=2. Figure 1The system includes a first beam splitter assembly 81, a second beam splitter assembly 82, and a third beam splitter assembly 83. The first and second beam splitter assemblies include a mirror and a polarizing beam splitter, which can be positioned along the optical path to sequentially reflect the received M-beam interference light. The third beam splitter assembly includes a polarizing beam splitter.

[0088] According to an embodiment of this utility model, the M-beams of phase-locked light from the (i+1)th stage interferometer are reflected by the i-th stage output component and then pass through the i-th beam splitter. Between the (i+1)th stage interferometer and the i-th beam splitter, the m-th phase-locked light and the m-th interference light share a common optical path. Combined with... Figure 1 The M-beams of phase-locked light from the second-stage interferometer 12 are reflected by the first-stage output component 61 and pass through the first beam splitter 81; between the second-stage interferometer 12 and the first beam splitter 81, the m-th phase-locked light and the m-th interference light propagate along the same optical path. The M-beams of phase-locked light from the third-stage interferometer 13 are reflected by the second-stage output component 32 and pass through the second beam splitter; between the second-stage interferometer 12 and the second beam splitter 82, the m-th phase-locked light and the m-th interference light propagate along the same optical path.

[0089] The optical quantum interference device also includes N phase-locked loop components. Figure 1 The example described uses two phase-locked loop (PLL) components: a first PLL component 101 and a second PLL component 102. The i-th PLL component includes a beam-splitting module 111, a beam-combining module 112, a transmission module 113, and an adjustment module 114. The beam-splitting module 111 is used to split externally incident light into M reference beams. The beam-combining module 112 is used to combine the M reference beams and the M PLLs transmitted through the i-th beam-splitting component to obtain the M-th second combined beam, wherein the m-th reference beam and the m-th PLL transmitted through the i-th beam-splitting component are combined to obtain the m-th second combined beam. The transmission module 113 is used to transmit the M second combined beams. The adjustment module 114 is used to adjust the optical path of the m-th parametric beam incident on the (i+1)-th interferometer component according to the optical power of the m-th second combined beam, thereby fixing the phase of the m-th parametric beam incident on the (i+1)-th interferometer component.

[0090] Figure 7 A partial structural diagram of the first phase-locked assembly provided according to an embodiment of the present invention is shown.

[0091] Figure 8 A schematic diagram of another part of the structure of the first phase-locked assembly provided according to an embodiment of the present invention is shown.

[0092] Combination Figure 1 and Figure 7 and Figure 8The following explanation uses the first phase-locked assembly between the first-stage interference assembly 11 and the second-stage interference assembly 12 as an example. Figure 1 As shown, the first-stage fiber delay array 21 is located between the first-stage interference component 11 and the second-stage interference component 12. (As shown...) Figure 8 As shown, the M (e.g., 16) delay rings of the first fiber delay array 21 are represented as 1st…16th, respectively. An incident beam with a wavelength of 1550nm is split into M reference beams with a wavelength of 1550nm by the beam splitting module 111. The beam combining module 112 is adapted to combine the M reference beams and the M phase-locked beams transmitted through the first beam splitting component to obtain the Mth second combined beam, wherein the mth reference beam and the mth phase-locked beam transmitted through the i-th beam splitting component are combined to obtain the mth second combined beam; the transmission module 113 is adapted to transmit the M second combined beams. The transmission module includes a transmission collimator array 1131 composed of M transmission collimators and a third mirror array 1132 composed of M mirrors. The third mirror array 1132 is disposed on an adjustment platform, which is used to adjust the pose of multiple mirrors in the third mirror array 1132.

[0093] The adjustment module includes M sub-adjustment modules. The m-th adjustment sub-module is used to adjust the optical path of the m-th parametric beam incident on the (i+1)-th interferometer component according to the optical power of the m-th second combined beam, thereby fixing the phase of the m-th parametric beam incident on the (i+1)-th interferometer component. The sub-adjustment module includes: two first phototubes 114-1, a second half-wave plate 114-2, a second polarization beam splitting unit 114-3, and a modulation unit 114-4. For the m-th sub-adjustment module, the second half-wave plate 114-2 is used to change the polarization direction of the m-th second combined beam, the second polarization beam splitting unit 114-3 is used to split the m-th second combined beam into two beams, and the two first phototubes 114-1 are used to detect the power of the two beams split from the m-th second combined beam, respectively. The detection results are used to control the modulation unit to adjust the optical path of the m-th parametric beam.

[0094] Referring again to the figure, a collimator 114-5 is also provided between the second half-wave plate 114-2 and the first polarization beam splitter 114-3 for collimating the beam output from the second half-wave plate. The aforementioned adjustment module also includes a phase-locked optical control unit 114-6 for controlling the phase-locked optical beam.

[0095] According to an embodiment of the present invention, both the first-stage interference component and the second-stage interference component include a triangular interference module.

[0096] Figure 9 A schematic diagram of a triangular interference module provided according to an embodiment of the present invention is shown.

[0097] like Figure 9As shown, the water-cooled circulating temperature control plate 122 is located on the vibration isolation plate 121, and the ultra-low expansion glass 123 is located on the water-cooled circulating temperature control plate 122. The triangular interference module includes a first triangular interferometer 125, a square reflector 126, and a second triangular interferometer 127. The entire triangular interference module is fixed to the ultra-low expansion glass 123 by UV-cured adhesive. The ultra-low expansion glass serves as a supporting substrate, reducing the impact of ambient temperature changes on the component position; the water-cooled circulating temperature control plate, through continuous temperature control, suppresses the thermal expansion and contraction of components caused by temperature fluctuations, reducing optical path drift at the source and ensuring the interference accuracy of the two triangular interferometers.

[0098] The fused silica support 124 is tightly fixed to the upper surface of the ultra-low expansion glass 123. Its material not only possesses a low coefficient of thermal expansion similar to that of the ultra-low expansion glass, but also exhibits extremely high mechanical rigidity and surface flatness. A first triangular interferometer 125 is fixed to the fused silica support 124, and a second triangular interferometer 127 is located on the upper surface of the ultra-low expansion glass 123. A square reflector 126 receives and reflects the input M-beam parametric light. The M-beam parametric light passes sequentially through the first triangular interferometer 125 and then interferes with the second triangular interferometer 127, resulting in M-beam interference light. The square reflector 126 is fixed using the fused silica support 124; the triangular interferometer module occupies a small optical platform area and possesses high stability. (Reference) Figure 1 and Figure 6 Since the beam spacing in the beam array output by the interference component is on the order of mm, a second mirror array 42 is needed to expand these beams for subsequent experimental convenience. When i is greater than 1, the M interference beams output by the i-th stage interference component, after being expanded by the second mirror array 42 of the second stage output component, sequentially pass through the first planar circular mirror array 45 and the second waveplate array 44 of the i-th stage output component before entering the output collimator group 43. By adjusting the pose of each second waveplate group 441 in the second waveplate array 44, the polarization of light pulses in the same time mode is made consistent, thereby achieving interference.

[0099] The M-beam parametric array is transmitted through free space to the interferometer. After passing through the square reflector 126, the transmission direction changes to vertical. By applying an optical coating to the square reflector 126, its reflectivity can be increased to greater than 99.7%.

[0100] As attached Figure 9 As shown, a vertically propagating parallel beam array is incident on two triangular interferometers. The spatial modes interfere through beam splitters and phase plates inside the triangular interferometers, achieving a linear transformation U. spatial It can be expressed as equation (1).

[0101] (1).

[0102] Each matrix element , K≤M. Indicates amplitude; Indicates phase.

[0103] According to an embodiment of this invention, each stage of the fiber delay array also includes a temperature control component, suitable for maintaining the length of the M delay loops constant. By maintaining the length of the M delay loops constant, the temperature control component can precisely control the delay amount of each interference beam (the delay amount is directly related to the length of the delay loop). This avoids thermal expansion and contraction of the delay loops and length fluctuations caused by changes in ambient temperature, thereby preventing the delay amount from deviating from the preset value and ensuring that optical pulses of different time modes can meet synchronously in subsequent interference components, providing a core guarantee for the accuracy of spatiotemporal multiplexing interference.

[0104] Figure 10 A schematic diagram illustrating the programmability of the interference device provided according to an embodiment of the present invention is shown.

[0105] like Figure 10 As shown, the interference device of this utility model embodiment has high programmability: on the one hand, the parameters of the i-th stage interference components in the device can be reset through thermal control, and their interference logic and beam splitting characteristics can be flexibly adjusted; on the other hand, the phase adjustment of the beam can be achieved by means of the synergistic effect of the i-th stage fiber delay array and the (i-1)-th stage fiber delay array (by finely adjusting the delay amount to change the optical path) and the input pulse center frequency (by modulating the acousto-optic modulation component, and the frequency change is linked to adjust the optical wavelength), ultimately achieving a near-universal full-range phase control capability.

[0106] According to the embodiments of this utility model, the phase state inside each level of the interference components directly affects the accuracy of optical quantum computing and the results of quantum precision measurement. To accurately grasp this key state, a special phase calibration device is required.

[0107] Figure 11 A schematic diagram illustrating the principle and implementation of internal phase calibration of the interference component provided in this embodiment of the utility model.

[0108] Figure 11The core function is to accurately measure the internal phase distribution of a multimode optical quantum interference device (QFID). Laser 131 provides the base laser, which is converted into a linearly swept double-pulse array via a first acousto-optic modulator 132, a second acousto-optic modulator 133, a third acousto-optic modulator 134, a fourth acousto-optic modulator 135, and a fifth acousto-optic modulator 136. This linearly swept double-pulse array serves as the probe light. Fiber amplifier 136 compensates for light intensity loss during the generation of the linearly swept double-pulse array. Multiple third half-wave plates 137 in the optical path adjust the polarization direction of the beam, ensuring that the polarization of the probe light is orthogonal to the parametric light polarization in the interference device, preventing interference with the quantum light signal. Simultaneously, they match the polarization separation requirements of multiple second polarization beam splitters in the optical path, guaranteeing the independence of the probe light path.

[0109] Figure 11 The second reflector 138 is used to change the propagation direction of the beam, enabling the probe light to accurately enter the interferometer assembly, multiple second phototubes, and other subsequent devices according to the designed path, ensuring the smoothness and precise alignment of the entire probe light path. The mechanical optical switch 139 controls the on / off state and input path of the probe light, enabling time-division calibration in multiple modes. Specifically, it sequentially switches the input channel of the probe light for different input modes of the interferometer assembly, meeting the requirements for phase calibration of the interferometer network in all modes and improving the flexibility and controllability of the calibration process. The interferometer assembly 140, as the core location for probe light interference, allows the injected dual-pulse array to propagate along different paths. The optical path difference generates a phase difference, thus forming phase-sensitive interference fringes. The changes in the brightness of the fringes directly reflect the phase state inside the interferometer network and are the carrier of phase information generation. Multiple second phototubes 142 ( Figure 11 The phototube has 16 output modes (16 in total), corresponding to the 16 output modes of the interference component. These modes convert the interfered optical signal (intensity change) into an electrical signal, providing raw electrical signal data for subsequent digital signal processing. The multi-channel design allows simultaneous acquisition of phase correlation signals from multiple output modes, improving calibration efficiency. The analog-to-digital converter 141 converts the analog electrical signal output by the phototube into a digital signal, facilitating computer storage, analysis, and curve fitting of the interference fringe data. Ultimately, data processing is used to infer the internal phase of the interference network, making it a key device connecting physical signals and data computation.

[0110] As a second aspect of this utility model, a method for adjusting a spatiotemporally multiplexed optical quantum interference device is also provided, the method comprising operations S1 to S2.

[0111] In operation S1, N+1 level interference components and N level fiber delay arrays are placed sequentially, wherein the i-th level fiber delay array in the N-level fiber delay array is positioned between the i-th level interference component and the i+1 level interference component.

[0112] In operation S2, adjust the N+1 level interference component and the N level fiber delay array so that the output light obtained after the test light passes through the N+1 level interference component and the N level fiber delay array meets the preset performance index.

[0113] To make the objectives, technical solutions, advantages, and claims of this utility model clearer, the adjustment method of the optical quantum interference device of this utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0114] Another embodiment of this disclosure provides a method for constructing a multimode optical quantum interference device (IPD), which can be used to construct and test a spatiotemporally multiplexed IPD with multiple mode inputs and multiple mode outputs. This IPD is used for precisely measuring the linear transformation achieved by the input quantum state, such as in Gaussian color sampling experiments. The method specifically includes the following steps.

[0115] Step 1: Align the forward light signal input.

[0116] By utilizing the light source component 51, one channel with a power of I is output. in The optical signal, after passing through the (N+1)th stage output component, will be divided into 16 spatial modes. The power of each mode is measured as (I1, I2, I3, ..., I...). 16 The transmittance of the N+1 order interferometer is S = (I1 + I2 + I3 + ... + I...). m / 2 ) / I in By adjusting the angles of multiple collimators and the beam waist position in the interferometer, the light collection efficiency of each collimator can be maximized. Through repeated iterative adjustments of the collimators, the collection efficiency can be adjusted to greater than 94%.

[0117] Step 2: Align the reverse light signal input.

[0118] By reverse inputting optical signals into each of the N+1 level output components, adjusting the remaining components in the optical path, and measuring the optical path length, the optical path length difference between the multiple beams output from the i-th input component and the i+1 interferometer component is made less than 1 cm.

[0119] S3, re-input the forward light signal for alignment.

[0120] A positive light signal is input again into the first-stage interference component, and each stage output component is adjusted to ensure that the M beams of interference light output by each stage output component are evenly distributed.

[0121] S4, linear transformation of the measurement interferometer component.

[0122] For an interferometer component with M spatial modes, its transformation matrix can be represented as an M×M unitary matrix U. Each element of this matrix... It can be represented as ,in, , Indicates amplitude; Indicates phase. Amplitude The measurement method is as follows: Inject a calibrated beam of light with an intensity of [insert value here] into each input pattern k. The classic optical signal is obtained, and then the optical signal intensity of each output mode is measured simultaneously. The amplitude of the corresponding matrix element is... .

[0123] The multimode optical quantum interference network of this invention features high mode connectivity, meaning it can achieve connectivity of all input modes whose time mode difference is within the longest delay loop.

[0124] This invention discloses an expandable multi-mode photonic quantum interference device based on bulk optical components, which is used to realize photonic quantum interference between multiple modes and can be applied to fields such as Gaussian wavelet sampling photonic quantum computing and quantum precision measurement.

[0125] The number of modes of this invention is scalable in the disclosed embodiments. While ensuring the stability of the setup, it can significantly increase the number of input and output modes of the interferometer, which can meet the needs of larger-scale optical quantum computing and quantum precision measurement applications.

[0126] It should be noted that the embodiments and accompanying drawings are merely a 3-level 16-mode interferometer and the two-level delay loop array between them, but the number of modes of the interferometer and the number of cascaded modes are not limited to the embodiments.

[0127] The embodiments of the present invention have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of the present invention is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the present invention, and all such substitutions and modifications should fall within the scope of the present invention.

Claims

1. A spatiotemporal multiplexing optical quantum interference device, characterized in that, include: The N+1 stage interference components are each suitable for receiving M beams of parametric light, wherein the parametric light is pulsed light, each parametric light includes multiple light pulses transmitted in a time sequence, and each stage interference component is also suitable for causing the M light pulses received at the same time to interfere, thereby obtaining M beams of interference light. The N-level fiber delay array is configured such that the i-th level fiber delay array is positioned between the i-th level interference component and the (i+1)-th level interference component. Each level fiber delay array includes M delay loops, which delay the received M beams of interference light in a one-to-one correspondence. The delay amounts of the M delay loops are different. Among them, the M delayed interference beams output by the i-th stage fiber delay array are used as the M parametric beams input to the (i+1)-th stage interference component, where 1≤i≤N and M>1.

2. The optical quantum interference device according to claim 1, characterized in that, The optical quantum interference device also includes: N+1 level output components, wherein the i-th level output component in the N+1 level output components is suitable for receiving M beams of interference light output by the i-th level interference component, 1≤i≤N; Each level of output components includes: Adjust the platform; Multiple reflection modules are located on the adjustment platform and are suitable for reflecting the received M-beam interference light; The adjustment platform is suitable for adjusting the pose of multiple reflection modules to change the spacing of the M-beam interference beams; the M-beam interference beams output by the i-th stage output component are transmitted to the i-th stage fiber delay array.

3. The optical quantum interference device according to claim 1, characterized in that, The optical quantum interference device also includes: There are N+1 beam-splitting components, wherein the i-th beam-splitting component is adapted to reflect the M-beam interference light output by the i-th stage interference component to the i-th stage output component, and the N+1-th stage beam-splitting component is adapted to reflect the M-beam interference light output by the N+1-th stage interference component to the N+1-th stage output component.

4. The optical quantum interference device according to claim 1, characterized in that, The optical quantum interference device also includes: Light source components suitable for generating pump light: A beam splitter assembly suitable for splitting the pump light into M sub-pump lights; M optical parametric resonant cavities are used to perform downparametric conversion on a portion of each of the M sub-pump beams to obtain the M beams of parametric light; After the lower parameter conversion is completed, the remaining sub-pump light also includes M beams, and the remaining m-th sub-pump light and the m-th pulse light are output through the same optical path.

5. The optical quantum interference device according to claim 4, characterized in that, Also includes: Pre-locked loop assembly, including: There are M control modules, of which the m-th control module is suitable for receiving the m-th sub-pump light; A dichroic mirror is used to separate the remaining sub-pump light and the parametric light of the M-beam; and to transmit the parametric light of the M-beam to the first-stage interference component; The beam splitting unit is suitable for splitting external reference pump light into M beams; The beam combining unit is suitable for combining M remaining sub-pump beams and M reference pump beams to obtain M first combined beams, wherein the m remaining sub-pump beam and the m reference pump beam are combined to obtain the m first combined beam. M fiber polarization beam splitters, wherein the m-th fiber polarization beam splitter among the M fiber polarization beam splitters is suitable for splitting the m-th first combined beam into two sub-combined beams. M photoelectric detection units, wherein the m-th photoelectric detection unit is adapted to detect the two sub-beams split from the m-th first combined beam, and emits the m-th driving signal according to the detection results of each. The m-th driving signal is adapted to drive the m-th control module to adjust the optical path of the m-th sub-pump beam, thereby realizing the adjustment of the phase of the m-th parametric beam.

6. The optical quantum interference device according to claim 1, characterized in that, The M-beams of phase-locked light from the (i+1)th stage interference component are reflected by the i-th stage output component and then pass through the i-th beam splitter component; Between the (i+1)th level interference component and the i-th beam splitter component, the m-th phase-locked beam and the m-th interference beam are transmitted along the same optical path.

7. The optical quantum interference device according to claim 6, characterized in that, The optical quantum interference device further includes N phase-locked loop components, wherein the i-th phase-locked loop component includes: The beam splitter module is suitable for splitting incident light from the outside into M reference beams; A beam combining module is suitable for combining M beams of reference light and M beams of phase-locked light passing through the i-th beam splitter to obtain the M-th second beam combining light, wherein the m-th beam of reference light and the m-th beam of phase-locked light passing through the i-th beam splitter are combined to obtain the m-th second beam combining light. The transmission module is suitable for transmitting M second-beam combined optical signals. The adjustment module is adapted to adjust the optical path of the m-th parametric light incident on the (i+1)-th interference component according to the optical power of the m-th second combined beam, thereby fixing the phase of the m-th parametric light incident on the (i+1)-th interference component, where m≤M.

8. The optical quantum interference device according to claim 1, characterized in that, Each stage of the fiber delay array also includes a temperature control component, suitable for maintaining the length of the M delay loops unchanged.

9. The optical quantum interference device according to claim 1, characterized in that, Each output component also includes an output collimator group; the output collimator group includes M output collimators, and the M output collimators of the i-th output collimator group are used to collimate the M beams of interference light output by the i-th output component and transmit the collimated M beams of interference light to the M delay loops of the i-th stage fiber delay array.

10. The optical quantum interference device according to claim 1, characterized in that, The optical quantum interference device also includes: The N-level input component, wherein the i-th level input component is connected to the i-th level fiber delay array and is adapted to input the M-beams of delayed interference light output from the i-th level fiber delay array to the (i+1)-th level interference component.

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