Quantum Communication Methods

Abstract

The present disclosure provides a quantum communication method. The method includes using a central controller to obtain a service matrix composed of multiple communication service information, the communication service information including a transmitter, a receiver, and multiple initial entangled connection numbers; solving a linear programming problem function to obtain a target entangled connection number corresponding to each communication service information; constructing a quantum communication network based on the multiple target entangled connection numbers and multiple entangled link numbers, wherein the position and number of entangled photon sources are determined based on the target entangled connection numbers; using the central controller to respond to an entangled connection request, constructing a first entangled route corresponding to the entangled connection request and multiple first entangled links corresponding to the first entangled route, the first entangled link including communication links formed between multiple first target repeaters and a target transmitter and a target receiver, respectively; and the target transmitter transmitting transmission information to the target receiver using the first entangled route and the multiple first entangled links.

Description

Technical Field

[0001] The present disclosure relates to the field of quantum communication technology, and more particularly, to a quantum communication method. Background Art

[0002] A quantum entanglement distribution system leverages the properties of quantum entanglement to distribute photons in an EPR (Electronic Precision Ratio) (EPR) entangled state to the source and destination nodes of a communication request. Currently, quantum computers are primarily used to achieve encrypted, secure communications and solve complex problems such as large-scale factorization and the discrete logarithm problem. To achieve this, one quantum computer must establish a quantum entanglement connection with another. Specifically, each quantum computer must store a photon in an EPR entangled state to communicate or compute. Therefore, in a quantum entanglement distribution system, photons must be distributed to the corresponding quantum computers via physical links. However, due to factors such as link absorption and signaling protocols, the success rate of photon transmission decreases exponentially with transmission distance. To overcome this limitation, it is necessary to connect quantum computers and quantum repeaters to form a quantum data network to support distributed quantum computing and improve the success rate of establishing entanglement connections.

[0003] In the process of realizing the concept of the present disclosure, the inventors discovered that there are at least the following problems in the related art: the existing process of establishing entangled routing takes a long time, and the related technology will change the position of the entangled photon source in real time, thereby increasing communication delay. Summary of the Invention

[0004] In view of this, an embodiment of the present disclosure provides a quantum communication method, including:

[0005] A service matrix composed of a plurality of communication service information is obtained by a central controller, wherein the communication service information includes a transmitting end, a receiving end, and a plurality of initial entangled connection numbers;

[0006] Solving a linear programming problem function using a linear programming solver to obtain a target number of entangled connections corresponding to each of the communication service information, wherein the linear programming problem function is constructed based on the service matrix;

[0007] Constructing a quantum communication network based on the plurality of target entangled connection numbers and the plurality of entangled link numbers, wherein the quantum communication network includes the plurality of transmitters, the plurality of receivers, the plurality of repeaters, and at least one entangled photon source connected to the repeaters, wherein the positions and numbers of the entangled photon sources are determined based on the target number of entangled connections;

[0008] In response to the entanglement connection request, the central controller constructs a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, wherein the first entanglement route includes a target transmitting end and a target receiving end, and the first entanglement links include communication links respectively formed between a plurality of first target repeaters and the target transmitting end and the target receiving end;

[0009] The target sending end transmits the transmission information to the target receiving end by using the first entangled route and the plurality of first entangled links.

[0010] According to an embodiment of the present disclosure, a linear programming problem function is solved using a linear programming solver to obtain a target number of entangled connections corresponding to each of the above communication service information, including:

[0011] The above linear programming problem function is processed based on the network flow conservation condition to obtain a relaxed linear programming problem function;

[0012] The above-mentioned linear programming solver is used to solve the above-mentioned relaxed linear programming problem function to obtain multiple above-mentioned target entanglement connection numbers.

[0013] According to an embodiment of the present disclosure, a quantum communication network is constructed based on a plurality of the above-mentioned target numbers of entangled connections, including:

[0014] For each of the communication service information, determining the number of entangled photon sources required for the communication service information according to the target number of entangled connections;

[0015] The above-mentioned number of entangled photon sources are distributed to the repeaters corresponding to the above-mentioned communication service information to complete the construction of the above-mentioned quantum communication network.

[0016] According to an embodiment of the present disclosure, the central controller determines, in response to an entanglement connection request, a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, including:

[0017] In response to the entanglement connection request, determining the target sending end, the target receiving end, and the target entanglement connection quantity;

[0018] Determining, by the central controller, the number of first entanglement links established between the first target repeater and the first target repeater and the target transmitting end and the target receiving end, respectively, according to the target transmitting end, the target receiving end, and the number of target entanglement connections;

[0019] The number of the first entangled links is sent to the first target repeater, so that the first target repeater constructs the first entangled links of the number mentioned above.

[0020] According to an embodiment of the present disclosure, the central controller is used to respond to an entanglement connection request to construct a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, further comprising:

[0021] storing resource allocation information corresponding to the entanglement connection request, the target transmitting end, the target receiving end, the target number of entanglement connections, the first target repeater, and the number of first entanglement links in the central controller; and / or

[0022] After the first target repeater successfully establishes the above number of first entangled links, it feeds back successful establishment information to the central controller.

[0023] According to an embodiment of the present disclosure, the quantum communication method further includes:

[0024] In a case where the number of entangled photons that can be transmitted by the first entangled links is less than the number of entangled photons required to be transmitted by the entangled connection request, determining at least one receiving end as a second target repeater;

[0025] determining a repeater associated with the at least one receiving end as a second target repeater;

[0026] respectively constructing a second entangled route and a plurality of second entangled links according to the target transmitting end, the plurality of second target repeaters and the target receiving end;

[0027] The target transmitting end is utilized to transmit the remaining entangled photons to the target receiving end through the second entangled routing and multiple second entangled links, wherein the remaining entangled photons represent the entangled photons remaining after the entangled photons required to be transmitted by the entangled connection request are transmitted by the first entangled link.

[0028] According to an embodiment of the present disclosure, the target transmitting end transmits the transmission information to the target receiving end using the first entangled route and the plurality of first entangled links, including:

[0029] The central controller determines a quantum node according to the first entangled link, wherein the quantum node includes the first target repeater;

[0030] Performing quantum entanglement exchange on the quantum nodes to splice the plurality of first entangled links into a target link;

[0031] The transmission information is transmitted to the target receiving end using the target link.

[0032] According to an embodiment of the present disclosure, when the number of the first target repeater is one, performing quantum entanglement exchange on the quantum node to splice multiple first entangled links into a target link includes:

[0033] generating two first photon pairs using an entangled photon source connected to the first target repeater, wherein the first photon pairs include an entangled first photon and a second photon;

[0034] Using the first target repeater, the first photons in the two first photon pairs are respectively sent to a target transmitting end and a target receiving end;

[0035] The above-mentioned first target repeater is used to perform quantum entanglement exchange on the second photon of the two first photon pairs to splice the first entangled link between the target transmitting end and the first target repeater and the first entangled link between the first target repeater and the target receiving end into a target link between the target transmitting end and the target receiving end.

[0036] According to an embodiment of the present disclosure, when the number of the first target repeaters is N, performing quantum entanglement exchange on the quantum nodes to splice the plurality of the first entangled links into a target link includes:

[0037] When i is not equal to N, generating a second photon pair using an entangled photon source connected to the i-th first target repeater, wherein the second photon pair includes an entangled third photon and a fourth photon;

[0038] Using the i-th first target repeater, the third photon is sent to the target transmitting end or the i-1-th first target repeater associated with the first target repeater;

[0039] Using the i-th first target repeater, perform quantum entanglement exchange on the first photon set or the second photon set to obtain a third entangled link, wherein the third entangled link represents a link between the target transmitter and the N-th first target repeater, the first photon set includes the third photon and the fourth photon, and the second photon set includes the fourth photon and the fifth photon;

[0040] When i is equal to N, generating two third photon pairs using an entangled photon source connected to the i-th first target repeater, wherein the third photon pairs include the entangled fifth photon and the sixth photon;

[0041] Using the i-th first target repeater, two fifth photons are sent to the i-1-th first target repeater and the target receiving end respectively;

[0042] The i-th first target repeater is used to perform quantum entanglement exchange on the two sixth photons to obtain a fourth entangled link, wherein the fourth entangled link represents a link between the target transmitting end and the target receiving end.

[0043] According to an embodiment of the present disclosure, transmitting the transmission information to the target receiving end using the target link includes:

[0044] Observing, using the target transmitting end, system state information between the first photon and the quantum bit received by the target transmitting end, wherein the quantum bit represents the transmitted information;

[0045] Transmitting the system status information to the target receiving end via the central controller or external computer, wherein the central controller or external computer is connected to the target sending end and the target sending end;

[0046] The target receiving end is used to obtain the quantum bit sent by the target transmitting end based on the first photon received by itself and the system state information.

[0047] According to embodiments of the present disclosure, a service matrix composed of multiple communication service information is modeled as a linear programming problem function. The target number of entangled connections for each communication service information can be determined from the linear programming problem function. This allows a quantum communication network to be constructed based on the target number of entangled connections. In this case, before the target transmitter begins sending transmission data, a corresponding first entangled route and first entangled link can be established to transmit the transmission information to the target receiver. Because the entangled photon source is placed at a fixed position in the quantum communication network before transmission, an entangled connection with minimal communication delay can be quickly established under any entangled connection request, ensuring good network throughput. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0049] Figure 1 The flowchart of the quantum communication method according to the embodiment of the present disclosure is schematically shown;

[0050] Figure 2 The following schematically shows a framework diagram of an initial quantum data network according to an embodiment of the present disclosure;

[0051] Figure 3 The figure schematically shows a framework diagram of a quantum communication network according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0052] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present disclosure. In the detailed description below, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0053] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise," "include," etc. used herein indicate the presence of the features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0054] 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 should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0055] When expressions such as "at least one of A, B and C, etc." are used, they should generally be interpreted in accordance with the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0056] A quantum data network typically consists of a quantum network component and a classical network component. The quantum network component primarily includes quantum computers, quantum repeaters, optical fibers, and entangled photon sources. Quantum computers and quantum repeaters have similar structures and functions: both possess limited quantum memory for storing photons, can observe their states, and perform operations such as quantum entanglement exchange. They can be collectively referred to as quantum nodes. The primary difference is that quantum computers require entangled connections with other quantum computers, while quantum repeaters do not. Optical fibers are used to interconnect quantum nodes and provide the quantum channels necessary for photon transmission. Entangled photon sources are typically placed at quantum nodes to generate photon pairs in EPR entangled states for establishing entangled connections. Classical networks complement quantum networks, performing functions that quantum networks cannot, such as transmitting measurement results and control signals.

[0057] When establishing an entangled connection between two quantum nodes (distributing quantum entanglement), existing technologies usually first find a path from the source node to the destination node (called entanglement routing); then the quantum nodes on the path use entangled photon sources to generate photons and distribute them to adjacent nodes, thereby establishing several entangled links (or called external connections) on each edge of the path; finally, the intermediate nodes on the path perform quantum entanglement exchange, splicing the entangled links into an end-to-end entangled connection.

[0058] In the above process, existing technologies assume that each node has sufficient entangled photon sources, or dynamically change the location of entangled photon sources based on connection requests when the number of entangled photon sources is limited. However, due to the high cost of entangled photon sources, they are difficult to deploy on a large scale. At the same time, changing the location of entangled photon sources will result in very large communication delays. In addition, related technologies require online calculation of different entangled routes for different connection requests, which makes it relatively time-consuming to establish entangled connections. Therefore, it is difficult to apply this technology to quantum entanglement distribution.

[0059] In view of this, an embodiment of the present disclosure provides a quantum communication method. The method includes using a central controller to obtain a service matrix composed of multiple communication service information, wherein each communication service information includes a transmitter, a receiver, and multiple initial entangled connection numbers; using a linear programming solver to solve a linear programming problem function to obtain a target entangled connection number corresponding to each communication service information, wherein the linear programming problem function is constructed based on the service matrix; constructing a quantum communication network based on the multiple target entangled connection numbers, wherein the quantum communication network includes multiple transmitters, multiple receivers, multiple repeaters, and at least one entangled photon source connected to the repeaters, and the positions and numbers of the entangled photon sources are determined based on the target entangled connection numbers; using the central controller to respond to an entangled connection request, constructing a first entangled route corresponding to the entangled connection request and multiple first entangled links corresponding to the first entangled route, wherein the first entangled route includes a target transmitter and a target receiver, and the first entangled link includes communication links formed between multiple first target repeaters and the target transmitter and the target receiver respectively; the target transmitter transmits transmission information to the target receiver using the first entangled route and the multiple first entangled links.

[0060] Figure 1 The flowchart of the quantum communication method according to the embodiment of the present disclosure is schematically shown.

[0061] like Figure 1 As shown, the quantum communication method includes operations S101 to S105.

[0062] In operation S101, a central controller is used to obtain a service matrix consisting of a plurality of communication service information, wherein one communication service information includes a transmitting end, a receiving end, and a plurality of initial entangled connection numbers;

[0063] In operation S102, a linear programming problem function is solved using a linear programming solver to obtain a target number of entangled connections corresponding to each communication service information, wherein the linear programming problem function is constructed based on the service matrix;

[0064] In operation S103, a quantum communication network is constructed based on the multiple target entangled connection numbers and the multiple entangled link numbers, wherein the quantum communication network includes multiple transmitting terminals, multiple receiving terminals, multiple repeaters, and at least one entangled photon source connected to the repeaters, and the positions and numbers of the entangled photon sources are determined based on the target entangled connection numbers;

[0065] In operation S104, a central controller is used to construct, in response to the entanglement connection request, a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, wherein the first entanglement route includes a target transmitting end and a target receiving end, and the first entanglement link includes communication links respectively formed between the plurality of first target repeaters and the target transmitting end and the target receiving end;

[0066] In operation S105 , the target transmitting end transmits transmission information to the target receiving end by using the first entangled route and the plurality of first entangled links.

[0067] According to an embodiment of the present disclosure, communication service information can be constructed based on the actual number of sending ends and receiving ends. For example, a communication service information can be constructed for sending end 1 and receiving end 1, wherein the communication service information corresponds to multiple initial entanglement connection numbers, and the initial entanglement connection number can be an integer such as 1, 2, 3, etc.

[0068] According to an embodiment of the present disclosure, multiple communication service information are constructed into a corresponding service matrix, so that the coverage network corresponding to the service matrix is ​​modeled into a linear programming problem function, and then the linear programming problem function is solved using a linear programming solver to obtain a function solution, which includes a limit on the number of entangled connections for each communication service information, that is, the target number of entangled connections.

[0069] According to the embodiments of the present disclosure, after determining the target number of entangled connections for each communication service message, a corresponding number of entangled photon sources can be set up on the repeaters between the transmitter and receiver based on the target number of entangled connections. For example, if the target number of entangled connections is two, two entangled photon sources can be set up on the repeaters between the transmitter and receiver. This allows the construction of a quantum communication network.

[0070] According to an embodiment of the present disclosure, after the construction is complete, the transmitter sends an entanglement connection request to the central controller. In response to the request, the central controller constructs a corresponding first entanglement route and multiple first entanglement links corresponding to the first entanglement route, for example, the first entanglement link between transmitter 1 and repeater 1, the first entanglement link between repeater 1 and receiver 1, and the first entanglement route between transmitter 1 and receiver 1. After this, the transmission information sent by transmitter 1 can be transmitted to receiver 1 via the first entanglement route and the first entanglement link.

[0071] According to embodiments of the present disclosure, a service matrix composed of multiple communication service information is modeled as a linear programming problem function. The target number of entangled connections for each communication service information can be determined from the linear programming problem function. This allows a quantum communication network to be constructed based on the target number of entangled connections. In this case, before the target transmitter begins sending transmission data, a corresponding first entangled route and first entangled link can be established to transmit the transmission information to the target receiver. Because the entangled photon source is placed at a fixed position in the quantum communication network before transmission, an entangled connection with minimal communication delay can be quickly established under any entangled connection request, ensuring good network throughput.

[0072] According to an embodiment of the present disclosure, a linear programming problem function is solved using a linear programming solver to obtain a target number of entangled connections corresponding to each communication service information, including:

[0073] The linear programming problem function is processed based on the network flow conservation condition to obtain the relaxed linear programming problem function;

[0074] The relaxed linear programming problem function is solved using a linear programming solver to obtain multiple target entanglement connection numbers.

[0075] According to an embodiment of the present disclosure, the linear programming problem function is an integer linear programming problem. However, there cannot be decimals for the target number of entangled connections in a quantum communication network. Therefore, it is necessary to remove the integer constraints in the planning problem and process it using network traffic conservation conditions, quantum resource constraints, etc., thereby obtaining a relaxed linear programming problem function. The problem function is solved using a linear programming solver to obtain the target number of entangled connections corresponding to each communication service information, wherein the quantum resource constraints include, for example, the storage space of quantum nodes and the number of entangled photon sources.

[0076] Figure 2 The figure schematically shows a framework diagram of an initial quantum data network according to an embodiment of the present disclosure. Figure 3 The figure schematically shows a framework diagram of a quantum communication network according to an embodiment of the present disclosure.

[0077] According to an embodiment of the present disclosure, a quantum communication network is constructed based on multiple target entanglement connection numbers, including:

[0078] For each communication service information, determining the number of entangled photon sources required for the communication service information according to the target number of entangled connections;

[0079] Distribute a number of entangled photon sources to repeaters corresponding to communication business information to complete the construction of the quantum communication network.

[0080] According to an embodiment of the present disclosure, the target number of entangled connections is the number of photon pairs required. When the number of photon pairs is determined, the number of entangled photon sources required for the repeaters related to the communication service information is determined. This number of entangled photon sources is distributed to the repeaters corresponding to the communication service information, thereby completing the construction of the quantum communication network and maximizing the expected throughput of the network and the fairness between node pairs, where a node refers to any device among the transmitting end, the receiving end and the relay end.

[0081] According to the embodiments of the present disclosure, Figure 2 The initial quantum data network shown in the figure has three quantum computers Q1, Q2, and Q3 (any of which can be used as a transmitter or receiver) and three quantum repeaters R1, R2, and R3. Assume that only six entangled photon sources can be placed. By using the method disclosed in this disclosure, the entangled photon sources are assigned to the repeaters corresponding to the communication service information, thereby obtaining Figure 3 The quantum communication network shown.

[0082] It should be noted that Figure 3 Each triangle connected to the repeater R represents a source of entangled photons.

[0083] According to an embodiment of the present disclosure, a central controller is used to respond to an entanglement connection request to construct a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, including:

[0084] In response to the entanglement connection request, determining a target sending end, a target receiving end, and a target number of entanglement connections;

[0085] Determining, by a central controller, the number of first entanglement links established between the first target repeater and the first target repeater and the target transmitting end and the target receiving end, respectively, according to the target transmitting end, the target receiving end, and the number of target entanglement connections;

[0086] The number of the first entanglement links is sent to the first target repeater, so that the first target repeater constructs the number of the first entanglement links.

[0087] According to an embodiment of the present disclosure, when the target transmitting end in the quantum communication network sends an entanglement connection request, the central controller determines the corresponding target receiving end and the number of entanglement connections to be sent this time based on the entanglement connection request, thereby determining the number of first entanglement links established between every two adjacent nodes (i.e., the first target repeater and the target transmitting end and the target receiving end respectively), and the central controller sends it to the corresponding node (i.e., the first target repeater), thereby enabling the first target repeater to establish a corresponding number of first entanglement links.

[0088] According to an embodiment of the present disclosure, a central controller is used to respond to an entanglement connection request to construct a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, further comprising:

[0089] storing resource allocation information corresponding to the entanglement connection request, the target sending end, the target receiving end, the target number of entanglement connections, the first target repeater, and the number of first entanglement links in the central controller; and / or

[0090] After the first target repeater successfully constructs the first number of entangled links, successful construction information is fed back to the central controller.

[0091] According to an embodiment of the present disclosure, in the process of allocating resources, the central controller determines the resource allocation information such as the entanglement connection request, the corresponding target transmitter, the target receiver, the number of target entanglement connections, the first target repeater, and the number of first entanglement links, and stores them in the central controller in the form of a log.

[0092] According to an embodiment of the present disclosure, after the first target repeater and other nodes successfully establish the first entanglement link, each node needs to feedback to the central controller whether it is successful, so that the central controller can send transmission information after determining that all relevant nodes have successfully established the entanglement link.

[0093] In one embodiment, a node establishes a first entangled link via an entangled photon source. For example, on a first entangled route (Q1, R1, Q2), the first entangled links created are (Q1, R1) and (R1, Q2), respectively. The successful establishment of the first entangled link is then fed back to the central controller.

[0094] According to an embodiment of the present disclosure, the quantum communication method further includes:

[0095] In a case where the number of entangled photons that can be transmitted by the first entangled link is less than the number of entangled photons that need to be transmitted for the entangled connection request, determining at least one receiving end as a second target repeater;

[0096] determining a repeater associated with at least one receiving end as a second target repeater;

[0097] respectively constructing a second entangled route and a plurality of second entangled links according to the target transmitting end, the plurality of second target repeaters, and the target receiving end;

[0098] The target transmitting end is used to transmit the remaining entangled photons to the target receiving end through the second entanglement route and multiple second entanglement links, wherein the remaining entangled photons represent the entangled photons remaining after the entangled photons required to be transmitted by the entanglement connection request are transmitted by the first entanglement link.

[0099] According to an embodiment of the present disclosure, for example, if transmitter Q1 wants to send entangled photons to receiver Q2, that is, the first entangled route is (Q1, R1, Q2), if the number of entangled photons that can be transmitted by the first entangled link is less than the number of entangled photons required to transmit the entangled connection request, and the quantum resources of another receiver Q3 are relatively abundant, in order to fully utilize the quantum resources and improve the network throughput, the central controller calculates the second entangled route online based on the remaining quantum resources. Assume that the obtained second entangled route is (Q1, R3, Q3, R2, Q2), where receiver Q3 and repeaters R3 and R2 are determined as the second target repeaters. (Q1, R3), (R3, Q3), (Q3, R2), and (R2, Q2) are all second entangled links.

[0100] The central controller then calculates the number of entanglements that repeaters R3 and R2 should distribute, that is, the number of entanglement links (Q1, Q3) and (Q3, Q2) created respectively, so as to use the second entanglement route to send the entangled photons that the first entanglement route cannot send.

[0101] In one embodiment, time can be divided into several segments. At the beginning of each segment, a service matrix may arrive, and the service requirements must be met as much as possible before the time runs out. Specifically, within a time period, the already calculated first entangled route is used to determine the entangled links that need to be built, but construction has not yet begun. The central controller calculates the second entangled route in real time based on the remaining resources, and then calculates the second entangled link based on this. Only then will the number of first and second entangled links built be sent to the relevant repeaters.

[0102] However, for some traffic matrices, even through the second entangled routing, it is not necessarily possible to successfully transmit all photons to the receiving end within this time period. In addition, the second entangled routing may contain multiple entangled paths.

[0103] According to an embodiment of the present disclosure, a target transmitting end transmits transmission information to a target receiving end using a first entangled route and a plurality of first entangled links, including:

[0104] The central controller determines a quantum node according to the first entangled link, wherein the quantum node includes a first target repeater;

[0105] performing quantum entanglement exchange on the quantum nodes to splice the plurality of first entangled links into a target link;

[0106] The target link is used to transmit the transmission information to the target receiving end.

[0107] According to an embodiment of the present disclosure, for multiple first entangled links, the corresponding quantum nodes are determined. For example, the first entangled links are (Q1, R1) and (R1, Q2). At this time, the determined quantum node is R1, which is sent to the first target repeater R1, thereby enabling the first target repeater R1 to perform quantum entanglement exchange, thereby splicing the first entangled links (Q1, R1) and (R1, Q2) into the target link (Q1, Q2). Thereafter, the target link (Q1, Q2) can be used to transmit the transmission information to the target receiving end.

[0108] In one embodiment, when the number of first target repeaters is one, performing quantum entanglement exchange on quantum nodes to splice multiple first entangled links into a target link includes:

[0109] generating two first photon pairs using an entangled photon source connected to a first target repeater, wherein the first photon pairs include an entangled first photon and a second photon;

[0110] using a first target repeater to transmit the first photons of the two first photon pairs to a target transmitting end and a target receiving end respectively;

[0111] The first target repeater is used to perform quantum entanglement exchange on the second photon of the two first photon pairs to splice the first entangled link between the target transmitting end and the first target repeater and the first entangled link between the first target repeater and the target receiving end into a target link between the target transmitting end and the target receiving end.

[0112] In another embodiment, the entangled photon source connected to the first target repeater generates only one photon pair, and sends the first photon and the second photon to the target transmitting end and the target receiving end respectively, thereby completing the establishment of the target link.

[0113] According to an embodiment of the present disclosure, when the number of first target repeaters is N, quantum entanglement exchange is performed on quantum nodes to splice multiple first entangled links into a target link, including:

[0114] When i is not equal to N, generating a second photon pair using an entangled photon source connected to the i-th first target repeater, wherein the second photon pair includes an entangled third photon and a fourth photon;

[0115] Using the i-th first target repeater, the third photon is sent to the target transmitting end or the i-1-th first target repeater associated with the first target repeater;

[0116] Using the i-th first target repeater to perform quantum entanglement exchange on the first photon set or the second photon set, obtaining a third entangled link, wherein the third entangled link represents a link between the target transmitting end and the N-th first target repeater, the first photon set includes the third photon and the fourth photon, and the second photon set includes the fourth photon and the fifth photon;

[0117] When i is equal to N, generating two third photon pairs using an entangled photon source connected to the i-th first target repeater, wherein the third photon pairs include an entangled fifth photon and a sixth photon;

[0118] Using the i-th first target repeater, two fifth photons are sent to the i-1-th first target repeater and the target receiving end respectively;

[0119] The i-th first target repeater is used to perform quantum entanglement exchange on the two sixth photons to obtain a fourth entangled link, wherein the fourth entangled link represents a link between the target transmitting end and the target receiving end.

[0120] According to an embodiment of the present disclosure, transmitting transmission information to a target receiving end using a target link includes:

[0121] Utilizing the target transmitting end to observe the system state information between the first photon received by itself and the quantum bit, wherein the quantum bit represents the transmitted information;

[0122] transmitting the system status information to a target receiving end via a central controller or an external computer, wherein the central controller or the external computer is connected to the target sending end and the target sending end;

[0123] The target receiving end obtains the quantum bit sent by the target sending end based on the first photon received by itself and the system state information.

[0124] The embodiments of the present disclosure are described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present disclosure. Although each embodiment has been described separately above, this does not mean that the measures in each embodiment cannot be used in combination to advantage. The scope of the present disclosure is defined by the appended claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A quantum communication method, comprising: Acquiring, using a central controller, a service matrix composed of a plurality of communication service information, wherein the communication service information includes a transmitting end information, a receiving end information, and a plurality of initial entangled connection numbers; Solving a linear programming problem function using a linear programming solver to obtain a target number of entangled connections corresponding to each communication service information, wherein the linear programming problem function is constructed based on the service matrix; Constructing a quantum communication network based on the multiple target numbers of entangled connections and the multiple numbers of entangled links, wherein the quantum communication network includes the multiple transmitting ends, the multiple receiving ends, the multiple repeaters, and at least one entangled photon source connected to the repeaters, and the positions and numbers of the entangled photon sources are determined based on the target number of entangled connections; Determining, by the central controller, in response to an entanglement connection request, a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route, wherein the first entanglement route includes a target transmitting end and a target receiving end, and the first entanglement links include communication links formed between a plurality of first target repeaters and the target transmitting end and the target receiving end, respectively; The target transmitting end transmits transmission information to the target receiving end by using the first entangled route and the plurality of the first entangled links.

2. The method according to claim 1, wherein The linear programming problem function is solved using a linear programming solver to obtain the target number of entangled connections corresponding to each communication service information, including: Processing the linear programming problem function based on the network flow conservation condition to obtain a relaxed linear programming problem function; The relaxed linear programming problem function is solved using the linear programming solver to obtain a plurality of target entanglement connection numbers.

3. The method according to claim 1, wherein Constructing a quantum communication network based on a plurality of target entangled connection numbers, comprising: For each piece of communication service information, determining the number of entangled photon sources required for the communication service information according to the target number of entangled connections; The number of entangled photon sources is distributed to the repeaters corresponding to the communication service information to complete the construction of the quantum communication network.

4. The method according to claim 3, wherein: The method comprises: determining, by the central controller, in response to an entanglement connection request, a first entanglement route corresponding to the entanglement connection request and a plurality of first entanglement links corresponding to the first entanglement route. In response to the entanglement connection request, determining the target sending end, the target receiving end, and the number of entanglement connections; Determining, by the central controller, the number of first entanglement links established between the first target repeater and the first target repeater and the target transmitting end and the target receiving end respectively according to the target transmitting end, the target receiving end, and the number of entanglement connections; The number of the first entanglement links is sent to the first target repeater, so that the first target repeater constructs the number of first entanglement links.

5. The method according to claim 4, further comprising: storing resource allocation information corresponding to the entanglement connection request, the target sending end, the target receiving end, the target entanglement connection quantity, the first target repeater, and the quantity of the first entanglement link in the central controller; and / or After the first target repeater successfully establishes the number of first entangled links, successful establishment information is fed back to the central controller.

6. The method according to claim 4, further comprising: In a case where the number of entangled photons that can be transmitted by the number of first entangled links is less than the number of entangled photons that need to be transmitted for the entangled connection request, determining at least one receiving end as a second target repeater; determining a repeater associated with the at least one receiving end as a second target repeater; respectively constructing a second entangled route and a plurality of second entangled links according to the target transmitting end, the plurality of the second target repeaters and the target receiving end; The target transmitting end is used to transmit the remaining entangled photons to the target receiving end through the second entangled route and multiple second entangled links, wherein the remaining entangled photons represent the entangled photons remaining after the entangled photons required to be transmitted by the entangled connection request are transmitted by the first entangled link.

7. The method according to claim 1, wherein The target sending end transmits transmission information to the target receiving end by using the first entangled route and the plurality of the first entangled links, including: The central controller determines a quantum node according to the first entangled link, wherein the quantum node includes the first target repeater; Performing quantum entanglement exchange on the quantum nodes to splice a plurality of the first entangled links into a target link; The transmission information is transmitted to the target receiving end using the target link.

8. The method according to claim 7, wherein: When the number of the first target repeater is one, performing quantum entanglement exchange on the quantum node to splice a plurality of the first entangled links into a target link includes: generating two first photon pairs using an entangled photon source connected to the first target repeater, wherein the first photon pairs include an entangled first photon and a second photon; Using the first target repeater, the first photons in the two first photon pairs are respectively sent to a target transmitting end and a target receiving end; The first target repeater is used to perform quantum entanglement exchange on the second photon of the two first photon pairs to splice the first entangled link between the target transmitting end and the first target repeater and the first entangled link between the first target repeater and the target receiving end into a target link between the target transmitting end and the target receiving end.

9. The method according to claim 7, wherein: When the number of the first target repeaters is N, performing quantum entanglement exchange on the quantum nodes to splice a plurality of the first entangled links into a target link includes: When i is not equal to N, generating a second photon pair using an entangled photon source connected to the i-th first target repeater, wherein the second photon pair includes an entangled third photon and a fourth photon; Using the i-th first target repeater, the third photon is sent to a target transmitting end or an i-1-th first target repeater associated with the first target repeater; Performing quantum entanglement exchange on the first photon set or the second photon set using the i-th first target repeater to obtain a third entangled link, wherein the third entangled link represents a link between the target transmitting end and the N-th first target repeater, the first photon set includes the third photon and the fourth photon, and the second photon set includes the fourth photon and the fifth photon; When i is equal to N, generating two third photon pairs using an entangled photon source connected to the i-th first target repeater, wherein the third photon pairs include the entangled fifth photon and the sixth photon; Using the i-th first target repeater, two fifth photons are sent to the i-1-th first target repeater and the target receiving end respectively; The i-th first target repeater is used to perform quantum entanglement exchange on two sixth photons to obtain a fourth entangled link, wherein the fourth entangled link represents a link between the target transmitting end and the target receiving end.

10. The method according to claim 8, wherein Transmitting the transmission information to the target receiving end using the target link includes: Observing, by the target transmitting end, system state information between the first photon received by the target transmitting end and a quantum bit, wherein the quantum bit represents the transmitted information; transmitting the system status information to the target receiving end via the central controller or the external computer, wherein the central controller or the external computer is connected to the target sending end and the target transmitting end; The target receiving end is used to obtain the quantum bit sent by the target transmitting end according to the first photon received by itself and the system state information.

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