A quantum communication decoding chip and device

Abstract

The application provides a quantum communication decoding chip and device, relates to the technical field of quantum communication, and solves the problem of low decoding efficiency and high cost of decoding in the current quantum communication decoding device. The quantum communication decoding chip is introduced to receive polarized coded or phase coded or time mixed coded optical signals, and the quantum communication decoding chip is used to decode the received polarized coded or phase coded or time mixed coded optical signals. The quantum communication decoding chip is compatible with the decoding functions of polarized coded or phase coded or time mixed coded optical signals, and multiple decoding modes are organically combined together. The multiple decoding modes are switched, the decoding efficiency of the chip is improved, and the hardware cost of the chip is reduced.

Description

Technical Field

[0001] This invention relates to the field of quantum communication technology, and in particular to a quantum communication decoding chip and device. Background Technology

[0002] Quantum communication is a novel communication method that utilizes quantum superposition and entanglement effects to transmit information. It is a major development direction and frontier of contemporary communication technology. Compared with traditional communication technology, it can guarantee absolute security in principle, and therefore has attracted widespread attention from scientists.

[0003] Currently, commonly used encoding methods in optical quantum communication systems include polarization coding, time-bit phase coding, and time-bit hybrid coding. Polarization coding utilizes photon polarization to transmit information; its basic principle is to encode information by encoding photons in different polarization states. Time-bit phase coding is a time-axis-based coding method that encodes information onto the time delay of photons. Time-bit hybrid coding combines time-bit phase coding and time-bit interference coding, simultaneously encoding information onto the time delay and phase difference of two adjacent photons. These commonly used coding methods typically employ bulk or fiber optic structures for encoding or decoding. However, bulk and fiber optic structures are large and unstable; therefore, the future development direction is the integration and miniaturization of quantum communication systems.

[0004] Existing technology discloses a decoding device based on time-phase-polarization coding, which organically combines time-phase coding and polarization coding, enabling time-phase coding and polarization coding to be implemented on the same optical pulse signal, greatly improving the coding rate. At the same time, the organic combination of time-phase and polarization decoding greatly simplifies the decoding structure, and reduces the inherent loss at the decoding end by using unbalanced basis vector settings, achieving lossless decoding of time basis vectors or reducing the system time window. However, quantum communication has multiple coding methods such as polarization coding, time-bit phase coding, and time-bit hybrid coding. This device can only decode time-phase and polarization coding, and cannot decode multiple coding methods such as polarization coding, time-bit phase coding, and time-bit hybrid coding. The decoding efficiency is low, and additional chips are needed to decode the undecoding coding methods, resulting in high cost. Summary of the Invention

[0005] To address the problems of low decoding efficiency and high cost in current quantum communication decoding devices, this invention proposes a quantum communication decoding chip and device that organically combines multiple decoding methods, enabling switching between various decoding methods, improving the chip's decoding efficiency, and reducing the chip's hardware cost.

[0006] To achieve the above-mentioned technical effects, the technical solution of the present invention is as follows: A quantum communication decoding chip is configured to receive polarization-coded, phase-coded, or time-mixed coded optical signals and decode the received polarization-coded, phase-coded, or time-mixed coded optical signals.

[0007] Preferably, the quantum communication decoding chip includes a first grating, a first beam splitter, a second beam splitter, a first electrothermal phase shifter, a first decoding unit, a second decoding unit, a second grating, a third grating, a fourth grating, and a fifth grating. The output of the first grating is connected to the inputs of the first and second beam splitters via two silicon-based waveguides, respectively. The output of the first beam splitter is connected to the inputs of the first and second decoding units via two silicon-based waveguides, respectively. The first electrothermal phase shifter is disposed on one silicon-based waveguide connecting the first beam splitter and the second decoding unit. The output of the second beam splitter is connected to the inputs of the first and second decoding units via two silicon-based waveguides, respectively. The output of the first decoding unit is connected to the inputs of the second and third gratings via two silicon-based waveguides, respectively. The output of the second decoding unit is connected to the inputs of the fourth and fifth gratings via two silicon-based waveguides, respectively.

[0008] Preferably, the first decoding unit includes a third beamsplitter, a second electrothermal phase shifter, a fourth beamsplitter, a fifth beamsplitter, a sixth beamsplitter, a seventh beamsplitter, and an eighth beamsplitter; the input of the third beamsplitter is connected to the outputs of the first and second beamsplitters via two silicon-based waveguides, respectively; the output of the third beamsplitter is connected to the inputs of the fourth and eighth beamsplitters via two silicon-based waveguides, respectively; wherein the second electrothermal phase shifter is disposed on one silicon-based waveguide connecting the third and eighth beamsplitters; the output of the fourth beamsplitter is connected to the inputs of the fourth and eighth beamsplitters via two silicon-based waveguides. A silicon-based waveguide connects to the fifth beamsplitter, wherein the third electrothermal phase shifter is disposed on one silicon-based waveguide connecting the fourth and fifth beamsplitters; the output of the fifth beamsplitter is connected to the input of the sixth beamsplitter via two silicon-based waveguides, and the output of the sixth beamsplitter is connected to the seventh beamsplitter via two silicon-based waveguides, wherein the fourth electrothermal phase shifter is disposed on one silicon-based waveguide connecting the sixth and seventh beamsplitters; the output of the seventh beamsplitter is connected to the input of the eighth beamsplitter via one silicon-based waveguide, and the output of the eighth beamsplitter is connected to the inputs of the second and third gratings via two silicon-based waveguides respectively.

[0009] Preferably, the second decoding unit includes a ninth beamsplitter, a fifth electrothermal phase shifter, a tenth beamsplitter, a sixth electrothermal phase shifter, an eleventh beamsplitter, a twelfth beamsplitter, a seventh electrothermal phase shifter, a thirteenth beamsplitter, and a fourteenth beamsplitter; the input of the ninth beamsplitter is connected to the outputs of the first and second beamsplitters via two silicon-based waveguides, respectively; the output of the ninth beamsplitter is connected to the inputs of the tenth and fourteenth beamsplitters via two silicon-based waveguides, respectively; wherein the fifth electrothermal phase shifter is disposed on one silicon-based waveguide connecting the ninth and fourteenth beamsplitters; the output of the tenth beamsplitter is connected to the input of the first beamsplitter and the fourteenth beamsplitter via two silicon-based waveguides. The input terminal of the eleventh beam splitter, wherein the sixth electrothermal phase shifter is disposed on a silicon-based waveguide connecting the tenth and eleventh beam splitters; the output terminal of the eleventh beam splitter is connected to the input terminal of the twelfth beam splitter through two silicon-based waveguides, and the output terminal of the twelfth beam splitter is connected to the input terminal of the thirteenth beam splitter through two silicon-based waveguides, wherein the seventh electrothermal phase shifter is disposed on a silicon-based waveguide connecting the twelfth and thirteenth beam splitters; the output terminal of the thirteenth beam splitter is connected to the input terminal of the fourteenth beam splitter through a silicon-based waveguide, and the output terminal of the fourteenth beam splitter is connected to the input terminals of the fourth and fifth gratings through two silicon-based waveguides respectively.

[0010] Preferably, the quantum communication decoding chip decodes optical signals that are polarization-coded, phase-coded, or time-mixed coded. Specifically, the decoding operation involves adjusting the current flowing through the first, second, third, fourth, fifth, sixth, and seventh electrothermal phase shifters to set the phase offset of each phase shifter for decoding.

[0011] The present invention also proposes a quantum communication decoding device, comprising: a signal transmitting end, a first transmission optical fiber, and a quantum communication decoding chip. The signal transmitting end is connected to the quantum communication decoding chip through the first transmission optical fiber, and transmits a polarization-coded, phase-coded, or time-mixed coded optical signal to the quantum communication decoding chip. The quantum communication decoding chip decodes the polarization-coded, phase-coded, or time-mixed coded optical signal.

[0012] Preferably, the device further includes a second transmission optical fiber, a third transmission optical fiber, a fourth transmission optical fiber, a fifth transmission optical fiber, and a detection end. The detection end includes a first detector, a second detector, a third detector, and a fourth detector. The first detector is connected to the output end of the second grating via the second transmission optical fiber. The second detector is connected to the output end of the third grating via the third transmission optical fiber. The third detector is connected to the output end of the fourth grating via the fourth transmission optical fiber. The fourth detector is connected to the output end of the fifth grating via the fifth transmission optical fiber.

[0013] Preferably, when the quantum communication decoding chip receives the polarization-coded optical signal, the polarization-coded optical signal is... , , , One of the four quantum states, the first detector is in the quantum state of The optical signal response of the second detector to the quantum state is... The optical signal response of the third detector to the quantum state is... The fourth detector responds to the optical signal, and the quantum state is... The optical signal response.

[0014] Preferably, when the quantum communication decoding chip receives the phase-coded optical signal, the phase-coded optical signal is... , 、 、 One of the four quantum states; the first detector is for the quantum state. The optical signal response of the second detector to the quantum state is... The optical signal response of the third detector to the quantum state is... The fourth detector responds to the optical signal, and the quantum state is... The optical signal response.

[0015] Preferably, when the quantum communication decoding chip receives a time-mixed encoded optical signal, the time-mixed encoded optical signal is... , 、 、 One of the four quantum states; the first detector is for the quantum state. The optical signal response of the second detector to the quantum state is... The optical signal response of the third detector to the quantum state is... The fourth detector responds to the optical signal, and the quantum state is... The optical signal response.

[0016] Compared with the prior art, the beneficial effects of the technical solution of the present invention are: This invention proposes a quantum communication decoding chip and device. By introducing a quantum communication decoding chip, it enables the decoding of polarization-coded, phase-coded, or time-mixed coded optical signals emitted by the signal transmitter. This allows the quantum communication decoding chip to be compatible with decoding functions for polarization-coded, phase-coded, or time-mixed coded optical signals, avoiding the drawback of having to add extra chips to decode undecoding methods. It also saves device space. This invention organically combines multiple decoding methods, enabling switching between multiple decoding methods, improving decoding efficiency, and reducing costs. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the quantum communication decoding chip proposed in the embodiments of the present invention; Figure 2 This is a schematic diagram of the structure of a quantum communication decoding device proposed in an embodiment of the present invention; Figure 3 This is a first simplified structural diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 4 This is a first partial simplified diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 5 This is a second partial simplified diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 6 This is a simplified third partial diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 7 This represents a fourth partial simplified diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 8 This is a second simplified structural diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 9 This represents a fifth partial simplified diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 10 This is a simplified sixth partial diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 11 This is a simplified seventh partial diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 12 This represents an eighth partial simplified diagram of the quantum communication decoding chip proposed in this embodiment of the invention; Figure 13 This is a third simplified structural diagram of the quantum communication decoding chip proposed in this embodiment of the invention; 1. Signal transmitting end; 2. First transmission optical fiber; 3. Quantum communication decoding chip; 301. First grating; 302. First beam splitter; 303. Second beam splitter; 304. First electrothermal phase shifter; 305. First decoding unit; 3051. Third beam splitter; 3052. Second electrothermal phase shifter; 3053. Fourth beam splitter; 3054. Third electrothermal phase shifter; 3055. Fifth beam splitter; 3056. Sixth beam splitter; 3057. Fourth electrothermal phase shifter; 3058. Seventh beam splitter; 3059. Eighth beam splitter; 306. Second decoding unit; 3061. Ninth beam splitter; 3062. 3063. Fifth electrothermal phase shifter; 3064. Tenth beam splitter; 3065. Sixth electrothermal phase shifter; 3066. Eleventh beam splitter; 3067. Twelfth beam splitter; 3068. Seventh electrothermal phase shifter; 3069. Thirteenth beam splitter; 3060. Fourteenth beam splitter; 307. Second grating; 308. Third grating; 309. Fourth grating; 310. Fifth grating; 4. Second transmission fiber; 5. Third transmission fiber; 6. Fourth transmission fiber; 7. Fifth transmission fiber; 8. Detector end; 801. First detector; 802. Second detector; 803. Third detector; 804. Fourth detector. Detailed Implementation

[0018] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this patent. To better illustrate this embodiment, some parts of the accompanying drawings may be omitted, enlarged, or reduced, and do not represent actual dimensions. The descriptions of directions such as "up" and "down" are not intended to limit this patent. It is understandable to those skilled in the art that some well-known details may be omitted from the accompanying drawings; The positional relationships depicted in the accompanying drawings are for illustrative purposes only and should not be construed as limiting this patent. The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] Example 1 See Figure 1 This embodiment proposes a quantum communication decoding chip. The quantum communication decoding chip 3 receives optical signals with polarization encoding, phase encoding, or time hybrid encoding, and decodes the received optical signals with polarization encoding, phase encoding, or time hybrid encoding.

[0020] The quantum communication decoding chip 3 includes a first grating 301, a first beam splitter 302, a second beam splitter 303, a first electrothermal phase shifter 304, a first decoding unit 305, a second decoding unit 306, a second grating 307, a third grating 308, a fourth grating 309, and a fifth grating 310. The output of the first grating 301 is connected to the inputs of the first beam splitter 302 and the second beam splitter 303 via two silicon-based waveguides, respectively. The output of the first beam splitter 302 is connected to the first decoding unit 305 and the second decoding unit 306 via two silicon-based waveguides, respectively. The input terminal of 6, wherein the first electrothermal phase shifter 304 is disposed on a silicon-based waveguide connecting the first beam splitter 302 and the second decoding unit 306; the output terminal of the second beam splitter 303 is connected to the input terminals of the first decoding unit 305 and the second decoding unit 306 respectively through two silicon-based waveguides; the output terminal of the first decoding unit 305 is connected to the input terminals of the second grating 307 and the third grating 308 respectively through two silicon-based waveguides; the output terminal of the second decoding unit 306 is connected to the input terminals of the fourth grating 309 and the fifth grating 310 respectively through two silicon-based waveguides.

[0021] In this embodiment, by introducing a quantum communication decoding chip, the decoding of polarization-coded, phase-coded, or time-mixed coded optical signals emitted by the signal transmitter is realized. This enables the quantum communication decoding chip to be compatible with the decoding function of polarization-coded, phase-coded, or time-mixed coded optical signals, avoiding the drawback of decoding undecoding methods by adding extra chips. This saves device space. The present invention organically combines multiple decoding methods, realizes the switching of multiple decoding methods, improves the decoding efficiency of the chip, and reduces the hardware cost of the chip.

[0022] Example 2 See Figure 1The first decoding unit 305 includes a third beamsplitter 3051, a second electrothermal phase shifter 3052, a fourth beamsplitter 3053, a third electrothermal phase shifter 3054, a fifth beamsplitter 3055, a sixth beamsplitter 3056, a fourth electrothermal phase shifter 3057, a seventh beamsplitter 3058, and an eighth beamsplitter 3059. The input terminal of the third beamsplitter 3051 is connected to the output terminals of the first beamsplitter 302 and the second beamsplitter 303 via two silicon-based waveguides, respectively. The output terminal of the third beamsplitter 3051 is connected to the input terminals of the fourth beamsplitter 3053 and the eighth beamsplitter 3059 via two silicon-based waveguides, respectively. The second electrothermal phase shifter 3052 is disposed on one silicon-based waveguide connecting the third beamsplitter 3051 and the eighth beamsplitter 3059. The output terminal of the fourth beamsplitter 3053 is connected to the input terminal of the fourth beamsplitter 3053 and the eighth beamsplitter 3059 via two silicon-based waveguides. The output end is connected to the fifth beam splitter 3055 via two silicon-based waveguides, wherein the third electrothermal phase shifter 3054 is disposed on one silicon-based waveguide connecting the fourth beam splitter 3053 and the fifth beam splitter 3055; the output end of the fifth beam splitter 3055 is connected to the input end of the sixth beam splitter 3056 via two silicon-based waveguides, and the output end of the sixth beam splitter 3056 is connected to the seventh beam splitter 3058 via two silicon-based waveguides, wherein the fourth electrothermal phase shifter 3057 is disposed on one silicon-based waveguide connecting the sixth beam splitter 3056 and the seventh beam splitter 3058; the output end of the seventh beam splitter 3058 is connected to the input end of the eighth beam splitter 3059 via one silicon-based waveguide, and the output end of the eighth beam splitter 3059 is connected to the input ends of the second grating 307 and the third grating 308 via two silicon-based waveguides respectively.

[0023] The second decoding unit 306 includes a ninth beamsplitter 3061, a fifth electrothermal phase shifter 3062, a tenth beamsplitter 3063, a sixth electrothermal phase shifter 3064, an eleventh beamsplitter 3065, a twelfth beamsplitter 3066, a seventh electrothermal phase shifter 3067, a thirteenth beamsplitter 3068, and a fourteenth beamsplitter 3069. The input terminal of the ninth beamsplitter 3061 is connected to the output terminals of the first beamsplitter 302 and the second beamsplitter 303 via two silicon-based waveguides, respectively. The output terminal of the ninth beamsplitter 3061 is connected to the input terminals of the tenth beamsplitter 3063 and the fourteenth beamsplitter 3069 via two silicon-based waveguides, respectively. The fifth electrothermal phase shifter 3062 is disposed on one silicon-based waveguide connecting the ninth beamsplitter 3061 and the fourteenth beamsplitter 3069. The output terminal of the tenth beamsplitter 3061 is connected to the input terminals of the first beamsplitter 3062 and the fourteenth beamsplitter 3069 via two silicon-based waveguides. The waveguide connects to the input of the eleventh beamsplitter 3065, wherein the sixth electrothermal phase shifter 3064 is disposed on a silicon-based waveguide connecting the tenth beamsplitter 3061 and the eleventh beamsplitter 3065; the output of the eleventh beamsplitter 3065 is connected to the input of the twelfth beamsplitter 3066 through two silicon-based waveguides, and the output of the twelfth beamsplitter 3066 is connected to the input of the thirteenth beamsplitter 3068 through two silicon-based waveguides, wherein the seventh electrothermal phase shifter 3067 is disposed on a silicon-based waveguide connecting the twelfth beamsplitter 3066 and the thirteenth beamsplitter 3068; the output of the thirteenth beamsplitter 3068 is connected to the input of the fourteenth beamsplitter 3069 through a silicon-based waveguide, and the output of the fourteenth beamsplitter 3069 is connected to the inputs of the fourth grating 309 and the fifth grating 310 through two silicon-based waveguides respectively.

[0024] The quantum communication decoding chip 3 decodes optical signals that are polarization-coded, phase-coded, or time-mixed coded. Specifically, the decoding operation involves adjusting the current flowing through the first, second, third, fourth, fifth, sixth, and seventh electrothermal phase shifters 304, 3052, 3054, 3057, 3062, 3064, and 3067 respectively to set the phase offset of each phase shifter.

[0025] Example 3 See Figure 1 and Figure 2This embodiment proposes a quantum communication decoding device, including: a signal transmitting end 1, a first transmission optical fiber 2, and the quantum communication decoding chip 3. The signal transmitting end 1 is connected to the quantum communication decoding chip 3 through the first transmission optical fiber 2, and transmits polarization-coded, phase-coded, or time-mixed coded optical signals to the quantum communication decoding chip 3. The quantum communication decoding chip 3 decodes the polarization-coded, phase-coded, or time-mixed coded optical signals.

[0026] The quantum communication decoding device proposed in this embodiment further includes a second transmission fiber 4, a third transmission fiber 5, a fourth transmission fiber 6, a fifth transmission fiber 7, and a detection end 8. The detection end 8 includes a first detector 801, a second detector 802, a third detector 803, and a fourth detector 804. The first detector 801 is connected to the output end of the second grating 307 through the second transmission fiber 4. The second detector 802 is connected to the output end of the third grating 308 through the third transmission fiber 5. The third detector 803 is connected to the output end of the fourth grating 309 through the fourth transmission fiber 6. The fourth detector 804 is connected to the output end of the fifth grating 310 through the fifth transmission fiber 7.

[0027] When the quantum communication decoding chip 3 receives the polarization-coded optical signal, the polarization-coded optical signal is: , , , One of the four quantum states, the first detector 801 has a pair of quantum states. The optical signal response, the second detector 802 pairs quantum states are The optical signal response, the third detector 803 for quantum states is The optical signal response, the fourth detector 804 pairs quantum states are The optical signal response; By adjusting the current flowing through the second, third, fourth, sixth, and seventh electric phase shifters 3052, 3054, 3057, 3064, and 3067 respectively, the phase offset of these seven electric phase shifters is set to... ,Will Figure 1 The quantum communication decoding chip structure shown is simplified as follows: Figure 3 The first simplified structure shown is referred to in [reference]. Figure 2 and Figure 3 The specific process of decoding polarization-encoded optical signals by the quantum communication decoding chip 3 is as follows: First, if the polarization-coded optical signal is in a quantum state... After the optical signal enters the first grating 301, it goes through the next path and then passes through a third beam splitter 303 with a "one-in, two-out" configuration. The optical signal passing through the third beam splitter 303 is split into two paths with equal probability. Then, if the optical signal after passing through the third beam splitter 303 is selected... Measuring the basis vectors will then... Figure 2 The signals from the first detector 801 and the second detector 802 are read. At this time, only the second detector 802 may respond, thus reading the incoming optical signal. If the optical signal after passing through the third beam splitter 303 is selectively selected... Measuring the basis vectors will then... Figure 2 The signals from the third detector 803 and the fourth detector 804 are read, and at this time, both the third detector 803 and the fourth detector 804 may detect photons. For the other three , , The detection results for the polarization-encoded optical signal of the quantum state are similar to those described above, and will not be repeated here.

[0028] Next, the phase of the first electrothermal phase shifter 304 and the fifth electrothermal phase shifter 3062 is set so that... basis vectors can be used for For accurate detection of optical signals, see Figures 4-7 The specific phase setting process is as follows: for The optical signal, after passing through the first grating 301, if we select The basis vectors are measured to obtain the following: Figure 4 and Figure 5 The partial structure shown; to facilitate the description of the phase settings of the first electrothermal phase shifter 304 and the fifth electrothermal phase shifter 3062, the following is introduced: express , These are path codes, representing the entry and exit points of the optical signal, respectively. The mathematical expression is as follows:

[0029] The mathematical expression is

[0030] The ninth beam splitter (3061) and the twelfth beam splitter (3066) are both 2-input 2-output beam splitters (BS). The mathematical expression of a 2-input 2-output beam splitter (BS) is as follows:

[0031] in, Represents an imaginary number; the mathematical expression of the twelfth beam splitter (3066) is the same as that of the ninth beam splitter (3061); Therefore, see Figure 5 and Figure 6 The phases of the first electrothermal phase shifter 304 and the fifth electrothermal phase shifter 3062 are set as follows: ,but The following two conditions must be met:

[0032]

[0033] in, This represents the global phase of the output quantum state; for the above Solving the formula for the two satisfied conditions yields the result with the phase set as... , This will satisfy both of the above conditions.

[0034] When the quantum communication decoding chip 3 receives the phase-coded optical signal, the phase-coded optical signal is: , 、 、 One of the four quantum states; the first detector 801 has a pair of quantum states. The optical signal response, the second detector 802 pairs quantum states are The optical signal response, the third detector 803 for quantum states is The optical signal response, the fourth detector 804 pairs quantum states are The optical signal response; By adjusting the current flowing through the first, third, fourth, sixth, and seventh electric phase shifters 3064 and 3067 respectively, the phase offset of each electric phase shifter 304, 3054, 3057, 3064, and 3067 is set. ,Will Figure 2 The quantum communication decoding chip shown is simplified as follows: Figure 8 The second simplified structure shown describes the specific process of the quantum communication decoding chip 3 decoding the polarization-coded optical signal as follows: See Figure 8 ,first , 、 、 All four optical signals belong to Light, then After the light enters the first grating 301, it goes through the next path and then passes through a third beam splitter 303 with "one in and two out". The light signal after passing through the third beam splitter 303 is split into two paths with equal probability. See Figures 9-10 Then, if the optical signal passing through the third beam splitter 303 is selected... Measuring the basis vectors will then... Figure 1 The signals from the first detector 801 and the second detector 802 are read at this time. The optical signal only receives a response from the first detector 801. The optical signal only responds to the second detector 802, and the length of the non-equilateral interferometer is customized according to the delay in the coded signal light. For example, The optical signal passes through the third beam splitter 3051 and exhibits various characteristics. The appropriate response time window is selected by choosing one of the four detectors: the first detector 801, the second detector 802, the third detector 803, and the fourth detector 804. Take the long arm, In the case of a short-arm configuration, they can arrive simultaneously at the eighth beam splitter 3059, between the third beam splitter 3051 and the eighth beam splitter. The mathematical form is expressed as:

[0035] The mathematical form is expressed as:

[0036] After the optical signal passes through the third beam splitter 3051, The signal expression for an optical signal is:

[0037] The signal expression for an optical signal is:

[0038] Therefore, assuming the phase of the second electrothermal phase shifter 3052 is At the eighth beam splitter at position 3059 The following two conditions must be met:

[0039]

[0040] Regarding the above Solving the formula for the two satisfied conditions yields the result with the phase set as... =0 satisfies the above conditions.

[0041] See Figure 11 and Figure 12 If the optical signal after passing through the third beam splitter 303 is selected If the basis vectors are measured, then the readings will be... Figure 1 The signals from the third detector 803 and the fourth detector 804 at this time... The signal light was only responded to by the third detector, 803. The signal light was only responded to by the fourth detector, 804. and After the optical signal passes through the third beam splitter 3051, The signal expression is:

[0042] The signal expression is:

[0043] Therefore, assuming the phase of the fifth electrothermal phase shifter 3062 is At the eighth beam splitter at position 3059 The following two conditions must be met:

[0044]

[0045] Regarding the above Solving the formula for the two satisfied conditions yields the result with the phase set as... = This will satisfy the above conditions.

[0046] When the quantum communication decoding chip 3 receives the time-mixed encoded optical signal, the time-mixed encoded optical signal is: , 、 、 One of the four quantum states; the first detector 801 has a pair of quantum states. The optical signal response, the second detector 802 pairs quantum states are The optical signal response, the third detector 803 for quantum states is The optical signal response, the fourth detector 804 pairs quantum states are The optical signal response.

[0047] The phase offset of the first, second, third, fourth, sixth, and seventh electric phase shifters 3064 and 3067 is set by adjusting the current flowing through them respectively. The phase shift of the second electrothermal phase shifter 3052 is... The phase offset of the third electrothermal phase shifter 3054 and the fourth electrothermal phase shifter 3057 is... Phase, will Figure 2 The quantum communication decoding chip shown is simplified as follows: Figure 13 The third simplified structure shown is referred to in [reference]. Figure 1 and Figure 13 The specific process of decoding polarization-encoded optical signals by the quantum communication decoding chip 3 is as follows: first , 、 、 All four optical signals belong to Light, then After the light enters the first grating 301, it goes through the next path and then passes through a third beam splitter 303 with "one in and two out". The light signal after passing through the third beam splitter 303 is split into two paths with equal probability. Then, if the optical signal after passing through the third beam splitter 303 is selected... Measuring the basis vectors will then... Figure 1 The signals from the first detector 801 and the second detector 802 are read. At this time, the first detector 801 and the second detector 802 select a response time window. The optical signal only receives a response from the first detector 801. The optical signal that has passed through the third beam splitter 303 is only responded to by the second detector 802; if the optical signal that has passed through the third beam splitter 303 is selected... 、 Measuring the basis vectors will then... Figure 1 The signals from the third detector 803 and the fourth detector 804 are read at this time. The optical signal only received a response from the third detector, 803. The optical signal was only responded to by the fourth detector, 804. and After the optical signal passes through the third beam splitter 3051, The signal expression is:

[0048] The signal expression is:

[0049] Therefore, assuming the phase of the fifth electrothermal phase shifter 3062 is At the eighth beam splitter at position 3059 The following conditions must be met:

[0050]

[0051] Regarding the above Solving the formula for the two satisfied conditions yields the result with the phase set as... = This will satisfy the above conditions.

[0052] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A quantum communication decoding chip, characterized in that, The quantum communication decoding chip (3) is configured to receive polarization-coded, phase-coded, or time-mixed encoded optical signals and decode the received polarization-coded, phase-coded, or time-mixed encoded optical signals. The quantum communication decoding chip (3) includes a first grating (301), a first beam splitter (302), a second beam splitter (303), a first electrothermal phase shifter (304), a first decoding unit (305), a second decoding unit (306), a second grating (307), a third grating (308), a fourth grating (309), and a fifth grating (310). The output of the first grating (301) is connected to the inputs of the first beam splitter (302) and the second beam splitter (303) via two silicon-based waveguides, respectively. The output of the first beam splitter (302) is connected to the first decoding unit (305) and the second decoding unit (306) via two silicon-based waveguides, respectively. The input terminal of the element (306) is provided, wherein the first electrothermal phase shifter (304) is disposed on a silicon waveguide connecting the first beam splitter (302) and the second decoding unit (306); the output terminal of the second beam splitter (303) is connected to the input terminals of the first decoding unit (305) and the second decoding unit (306) through two silicon waveguides respectively; the output terminal of the first decoding unit (305) is connected to the input terminals of the second grating (307) and the third grating (308) through two silicon waveguides respectively; the output terminal of the second decoding unit (306) is connected to the input terminals of the fourth grating (309) and the fifth grating (310) through two silicon waveguides respectively. The first decoding unit (305) includes a third beam splitter (3051), a second electrothermal phase shifter (3052), a fourth beam splitter (3053), a third electrothermal phase shifter (3054), a fifth beam splitter (3055), a sixth beam splitter (3056), a fourth electrothermal phase shifter (3057), a seventh beam splitter (3058), and an eighth beam splitter (3059); the input terminal of the third beam splitter (3051) is connected to two silicon-based... Waveguides are connected to the outputs of the first beam splitter (302) and the second beam splitter (303), respectively. The output of the third beam splitter (3051) is connected to the inputs of the fourth beam splitter (3053) and the eighth beam splitter (3059) via two silicon-based waveguides. The second electrothermal phase shifter (3052) is located on one of the silicon-based waveguides connecting the third beam splitter (3051) and the eighth beam splitter (3059). The fourth beam splitter (3053) The output of the fourth beam splitter (3053) is connected to the fifth beam splitter (3055) via two silicon waveguides. The third electrothermal phase shifter (3054) is located on one silicon waveguide connecting the fourth beam splitter (3053) and the fifth beam splitter (3055). The output of the fifth beam splitter (3055) is connected to the input of the sixth beam splitter (3056) via two silicon waveguides. The output of the sixth beam splitter (3056) is connected to the seventh beam splitter via two silicon waveguides. The device (3058) includes a fourth electrothermal phase shifter (3057) located on a silicon waveguide connecting the sixth beam splitter (3056) and the seventh beam splitter (3058); the output of the seventh beam splitter (3058) is connected to the input of the eighth beam splitter (3059) via a silicon waveguide, and the output of the eighth beam splitter (3059) is connected to the inputs of the second grating (307) and the third grating (308) via two silicon waveguides respectively. The second decoding unit (306) includes a ninth beamsplitter (3061), a fifth electrothermal phase shifter (3062), a tenth beamsplitter (3063), a sixth electrothermal phase shifter (3064), an eleventh beamsplitter (3065), a twelfth beamsplitter (3066), a seventh electrothermal phase shifter (3067), a eleventh third beamsplitter (3068), and a fourteenth beamsplitter (3069); the input of the ninth beamsplitter (3061) is split through two silicon waveguides. The output terminals of the first beam splitter (302) and the second beam splitter (303) are not connected separately. The output terminal of the ninth beam splitter (3061) is connected to the input terminals of the tenth beam splitter (3063) and the fourteenth beam splitter (3069) through two silicon-based waveguides, respectively. The fifth electrothermal phase shifter (3062) is located on one of the silicon-based waveguides connecting the ninth beam splitter (3061) and the fourteenth beam splitter (3069). The output terminal of the tenth beam splitter (3063) is connected to the input terminals of the fourteenth beam splitter (3063) through two silicon-based waveguides. A silicon-based waveguide is connected to the input of the eleventh beamsplitter (3065), wherein the sixth electrothermal phase shifter (3064) is disposed on a silicon-based waveguide connecting the tenth beamsplitter (3063) and the eleventh beamsplitter (3065); the output of the eleventh beamsplitter (3065) is connected to the input of the twelfth beamsplitter (3066) through two silicon-based waveguides, and the output of the twelfth beamsplitter (3066) is connected to the input of the thirteenth beamsplitter (3066) through two silicon-based waveguides. 8) The input terminal of the seventh electrothermal phase shifter (3067) is located on a silicon waveguide connecting the twelfth beam splitter (3066) and the eleventh beam splitter (3068); the output terminal of the eleventh beam splitter (3068) is connected to the input terminal of the fourteenth beam splitter (3069) through a silicon waveguide, and the output terminal of the fourteenth beam splitter (3069) is connected to the input terminals of the fourth grating (309) and the fifth grating (310) through two silicon waveguides respectively; The quantum communication decoding chip (3) decodes optical signals that are polarization-coded, phase-coded, or time-mixed coded. Specifically, the decoding operation is as follows: the current flowing through the first electrothermal phase shifter (304), the second electrothermal phase shifter (3052), the third electrothermal phase shifter (3054), the fourth electrothermal phase shifter (3057), the fifth electrothermal phase shifter (3062), the sixth electrothermal phase shifter (3064), and the seventh electrothermal phase shifter (3067) is adjusted respectively to set the phase offset of the first electrothermal phase shifter (304), the second electrothermal phase shifter (3052), the third electrothermal phase shifter (3054), the fourth electrothermal phase shifter (3057), the fifth electrothermal phase shifter (3062), the sixth electrothermal phase shifter (3064), and the seventh electrothermal phase shifter (3067) for decoding.

2. A quantum communication decoding device, characterized in that, include: The signal transmitting end (1), the first transmission optical fiber (2) and the quantum communication decoding chip (3) as described in claim 1 are provided. The signal transmitting end (1) is connected to the quantum communication decoding chip (3) through the first transmission optical fiber (2) to transmit polarization-coded, phase-coded or time-mixed coded optical signals to the quantum communication decoding chip (3). The quantum communication decoding chip (3) decodes the polarization-coded, phase-coded or time-mixed coded optical signals.

3. The quantum communication decoding device according to claim 2, characterized in that, It also includes a second transmission fiber (4), a third transmission fiber (5), a fourth transmission fiber (6), a fifth transmission fiber (7), and a detection end (8). The detection end (8) includes a first detector (801), a second detector (802), a third detector (803), and a fourth detector (804). The first detector (801) is connected to the output end of the second grating (307) through the second transmission fiber (4). The second detector (802) is connected to the output end of the third grating (308) through the third transmission fiber (5). The third detector (803) is connected to the output end of the fourth grating (309) through the fourth transmission fiber (6). The fourth detector (804) is connected to the output end of the fifth grating (310) through the fifth transmission fiber (7).

4. The quantum communication decoding device according to claim 3, characterized in that, When the quantum communication decoding chip (3) receives the polarization-coded optical signal, the polarization-coded optical signal is: , , , One of the four quantum states, the first detector (801) for quantum state is The second detector (802) responds to the optical signal, and the quantum state is... The optical signal response of the third detector (803) to the quantum state is... The optical signal response of the fourth detector (804) to the quantum state is... The optical signal response.

5. The quantum communication decoding device according to claim 3, characterized in that, When the quantum communication decoding chip (3) receives the phase-coded optical signal, the phase-coded optical signal is: , 、 、 One of the four quantum states; the first detector (801) is for the quantum state of The second detector (802) responds to the optical signal, and the quantum state is... The optical signal response of the third detector (803) to the quantum state is... The optical signal response of the fourth detector (804) to the quantum state is... The optical signal response.

6. The quantum communication decoding device according to claim 3, characterized in that, When the quantum communication decoding chip (3) receives the time-mixed encoded optical signal, the time-mixed encoded optical signal is: , 、 、 One of the four quantum states; the first detector (801) is for the quantum state of The second detector (802) responds to the optical signal, and the quantum state is... The optical signal response of the third detector (803) to the quantum state is... The optical signal response of the fourth detector (804) to the quantum state is... The optical signal response.

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