Asymmetric bidirectional quantum teleportation method based on seven-quantum entanglement state
Through the asymmetric bidirectional quantum teleportation method based on seven quantum entangled states, the problems of high resource consumption and complex operation in the prior art are solved, and efficient quantum teleportation is achieved, which improves the feasibility and compatibility of the experiment.
Patent Information
- Application Number
- CN202411176918.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-26
- Publication Date
- 2024-12-06
AI Technical Summary
The existing bidirectional quantum teleport schemes have problems such as classical and quantum resource consumption, low intrinsic efficiency, complex operation and poor compatibility, which are difficult to implement in experiments.
Using an asymmetric bidirectional quantum teleportation method based on seven quantum entangled states, the initial seven single qubits are modified into seven qubit entangled states through logic gates, CNOT operation and Bell state basis measurement are performed, and the measurement is measured using classic channel transmission. As a result, recovery operations are performed to reconstruct the target quantum state, reducing the difficulty of execution and resource consumption of quantum teleportation.
It realizes a two-way asymmetric quantum teleportation without tripartite control, reduces measurement difficulty and resource consumption, improves transmission efficiency and compatibility, and has high experimental feasibility.
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Figure CN119094034A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of quantum communication technology, and in particular to an asymmetric seven-quantum entangled state-based Bidirectional quantum teleportation method. Background Art
[0002] Quantum teleportation is an important concept in quantum information science. It uses principles such as quantum entanglement and quantum measurement to realize the process of transmitting quantum information between entangled quantum bits. Unlike traditional classical communication methods, quantum teleportation can completely replicate an unknown quantum system state in another quantum system without directly transmitting the quantum bit itself. Quantum teleportation can not only transmit unknown quantum information non-locally, but also distribute quantum resources remotely. Therefore, since Bennett et al. creatively proposed the first quantum teleportation scheme in 1993, quantum teleportation has received considerable attention in both theoretical and experimental fields.
[0003] At the same time, many new developments related to quantum teleportation have been gradually reported. In 2011, Mishra et al. first proposed a bidirectional quantum communication concept called "secure quantum information exchange", which realized quantum communication in which two communicating parties simultaneously exchanged their own arbitrary unknown quantum states. In other words, under the framework of this quantum communication, the two communicating parties act as the sender and receiver of a quantum message, and also the receiver and sender of another quantum message. This quantum communication mode was later called bidirectional quantum state teleportation. Since then, various bidirectional quantum teleportation schemes have been proposed one after another.
[0004] However, most of the current bidirectional quantum teleportation schemes have problems such as high consumption of classical and quantum resources, low intrinsic efficiency, and complex operation. In addition, these schemes have poor compatibility and are difficult to implement in experiments. Summary of the invention
[0005] In view of the problems existing in the above-mentioned prior art, the present invention provides an asymmetric The bidirectional quantum teleportation method aims to reduce the difficulty of executing quantum teleportation, reduce the consumption of classical and quantum resources, and realize bidirectional asymmetric quantum teleportation without the need for three-party control.
[0006] To achieve the above object, the present invention provides an asymmetric Bidirectional quantum teleportation method, including:
[0007] S1, transform the initial seven single-qubit pure states through logic gates to prepare a seven-qubit entangled state;
[0008] S2, respectively populating the seven quantum bit particles in the seven-qubit entangled state to the first communication party and the second communication party, constructing a quantum physical system for quantum state transmission; the target quantum particle of the quantum state to be transmitted by the communication party and the prepared quantum particle obtained by the population together constitute the entangled particle owned by the communication party;
[0009] S3, the first communication party and the second communication party respectively perform CNOT operations on their respective target quantum particles;
[0010] S4, performing Bell state basis measurement on the entangled particles owned by the first communication party and the second communication party respectively to obtain a first measurement result and a second measurement result;
[0011] S5, the first communication party and the second communication party transmit the first measurement result and the second measurement result to the other communication party respectively through a classical channel;
[0012] S6, based on the received second measurement result and the first measurement result, the first communication party and the second communication party respectively perform recovery operations to reconstruct the target quantum state transmitted by the other communication party.
[0013] Furthermore, the steps for preparing the seven-qubit entangled state in step S1 are specifically as follows:
[0014] S11, seven single quantum bits with initial state |0> are combined into a seven-qubit direct product state
[0015]
[0016] S12, yes The middle qubits 1 and 2 perform a single-qubit Hadamard gate operation;
[0017] S13, perform CNOT operation on quantum bits (1,3), (1,5), (1,7), (2,4) and (2,6) to obtain a seven-qubit entangled state Among them, quantum bits 1 and 2 are control quantum bits, and quantum bits 3, 5, 7, 4, and 6 are target quantum bits.
[0018] Furthermore, the specific form of the Hadamard gate operation is:
[0019]
[0020] After performing the Hadamard gate operation, we get:
[0021]
[0022] The specific form of the CNOT operation is:
[0023]
[0024] Among them, m and n represent quantum bits, I = |0><0|+|1><1| is a unit operation, σ x =|0><1|+|1><0| is a Pauli operation;
[0025] The seven-qubit entangled state for:
[0026]
[0027] Furthermore, the step S2 of respectively populating the seven quantum bit particles in the seven quantum bit entangled state to the first communication party and the second communication party is specifically as follows:
[0028] The quantum bit particles (1, 2, 6) are distributed in the network nodes at the first communication party, and the quantum bit particles (3, 4, 5, 7) are distributed in the network nodes at the second communication party.
[0029] Further, the first target quantum state to be transmitted by the first communication party to the second communication party is an arbitrary three-qubit GHZ state, which is composed of target quantum particles (A1, A2, A3);
[0030] The second target quantum state to be transmitted by the second communication party to the first communication party is an arbitrary two-qubit Bell state composed of target quantum particles (B1, B2).
[0031] Furthermore, the step S3 specifically includes:
[0032] The first communication party performs a CNOT operation on the qubit pairs (A1, A2) and (A1, A3), where A1 is the control qubit and A2 and A3 are the target qubits;
[0033] The second communicating party performs a CNOT operation on the quantum bit pair (B1, B2), where B1 is the control quantum bit and B2 is the target quantum bit.
[0034] Furthermore, the step S4 specifically includes:
[0035] Selecting a target quantum particle and a prepared quantum particle from the entangled particles owned by the first communicating party to form a first entangled particle pair, and performing Bell state basis measurement on the first entangled particle pair to obtain a first measurement result;
[0036] A target quantum particle and a prepared quantum particle are selected from the entangled particles owned by the second communicating party to form a second entangled particle pair, and a Bell state basis measurement is performed on the second entangled particle pair to obtain a second measurement result.
[0037] Furthermore, the Bell state basis measurement basis vectors in step S4 are composed of four mutually orthogonal Bell states, which are:
[0038]
[0039] Furthermore, the step S5 specifically includes: converting the Bell state basis measurement result into 2-bit classical information according to the correspondence between the Bell state measurement result and the classical information for transmission through the classical channel;
[0040] The corresponding relationship between the Bell state measurement result and the classical information is:
[0041]
[0042] Furthermore, the step S6 specifically includes:
[0043] Perform two single-qubit unitary operations according to the received second measurement result and the prepared quantum particles of the first communication party that have not undergone Bell basis measurement, to reconstruct a second target quantum state transmitted by the second communication party;
[0044] Perform three single-qubit unitary operations according to the received first measurement result and the prepared quantum particles of the second communication party that have not undergone Bell basis measurement, to reconstruct the first target quantum state transmitted by the first communication party;
[0045] The single-qubit unitary operation is selected from the set of operations {I,σ x ,iσ y ,σ z},
[0046] Where I=|0><0|+|1><1| is a unit operation, σ x =|0><1|+|1><0| is the Pauli operation, iσ y =|0><1|-|1><0| is the Pauli operation, σ z =|0><0|-|1><1| is the Pauli operation.
[0047] An asymmetric method based on seven quantum entangled states of the present invention The bidirectional quantum teleportation method has the following beneficial effects:
[0048] 1. The present invention utilizes the operation of controlling the NOT gate to compress the quantum state information to be transmitted and integrate it into the quantum channel. It only needs to perform two Bell state measurements and some simple necessary quantum operations, and does not involve the measurement of multi-qubit entangled states of three or more qubits. Compared with the existing technology, the measurement and execution difficulty in the process is greatly reduced, less quantum resources and classical bits are consumed, and it has higher inherent efficiency.
[0049] 2. The seven-qubit entangled state prepared by the present invention can perform bidirectional quantum teleportation of the Bell state of any two qubits and the GHZ state of any three qubits, with strong compatibility and high experimental feasibility. BRIEF DESCRIPTION OF THE DRAWINGS
[0050] Figure 1 This invention is an asymmetric seven-quantum entangled state based on Schematic diagram of the process of bidirectional quantum teleportation method;
[0051] Figure 2 It is a quantum circuit schematic diagram of a preparation process of a seven-qubit entangled state channel provided by an embodiment of the present invention;
[0052] Figure 3 An embodiment of the present invention provides an asymmetric seven-qubit entangled state. Quantum circuit diagram of the two-way quantum teleportation method. DETAILED DESCRIPTION
[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0054] To facilitate understanding of this embodiment, the specific implementation of the present invention is further described below in conjunction with the accompanying drawings.
[0055] First, the technical problem to be solved by the present invention is briefly described.
[0056] The two communicating parties involved in the bidirectional quantum teleportation method of this embodiment are Alexis and Billy, where Alexis is the first communicating party and Billy is the second communicating party. Each communicating party is both a receiver and sender of an unknown quantum information, and also a sender and receiver of another unknown quantum information. Moreover, the two unknown quantum information of Alexis and Billy in this embodiment are asymmetric.
[0057] Specifically, in this embodiment, Alexis controls three entangled quantum bit particles (A1, A2, A3), which are in a first target quantum state, and this state is unknown to any party in the communication. Alexis needs to transmit the first target quantum state to Billy; Billy controls two entangled quantum bit particles (B1, B2), which are in a second target quantum state, and this state is unknown to any party in the communication. Billy needs to transmit the second target quantum state to Alexis.
[0058] Reference Figure 1 As shown in the flowchart, the quantum teleportation method provided by the present invention includes the following 6 steps:
[0059] S1, prepare the seven-qubit entangled state, the quantum circuit is as follows Figure 2 As shown, including:
[0060] S11, prepare seven single qubits, each qubit is in the quantum state |0>, and they constitute a seven-qubit direct product state:
[0061]
[0062] S12, performs a single-qubit Hadamard gate operation, i.e., H operation, on qubits 1 and 2. The effect of the Hadamard gate operation can be expressed as
[0063]
[0064] These two Hadamard gate operations make the initial seven-qubit direct product state Evolved into
[0065]
[0066] S13, perform five two-qubit controlled NOT gate operations, i.e., CNOT operations, on qubit pairs (1, 3), (1, 5), (1, 7), (2, 4), and (2, 6), where qubits 1 and 2 are control qubits, and qubits 3, 5, 4, 6, and 7 are target qubits. The effect of the two-qubit controlled NOT gate operation can be expressed as
[0067]
[0068] Among them, I=|0><0|+|1><1| is a unit operation, σ x =|0><1|+|1><0| is a Pauli operation. After these five control NOT gates, the quantum state It eventually transforms into a special seven-qubit entangled state:
[0069]
[0070] This seven-qubit entangled state can be used as a quantum channel. Through various operations of the communicating party, it can generate an entangled relationship with the target quantum particle to be transmitted, and then reflect the unknown quantum state of the target quantum particle.
[0071] Based on the method of the present invention, quantum channels are used Bidirectional quantum teleportation of any two-qubit Bell state and any three-qubit GHZ state can be performed. That is, the first target quantum state that can be transmitted is an arbitrary three-qubit GHZ state, including but not limited to:
[0072]
[0073] The second target quantum state that can be transmitted is an arbitrary two-qubit GHZ state, including but not limited to:
[0074]
[0075] Among them, α, β, U k 、V k , γ, δ, K, and L are complex coefficients and are unknown to anyone, including the two communicating parties Alexis and Billy themselves, and satisfy the relationship:
[0076] αα * +ββ * =1, γγ * +δδ * =1, KK * +LL * =1
[0077] In this embodiment, the first target quantum state is The second target quantum state is It should be noted that other target quantum states can also achieve teleportation by simply replacing them according to the following description, which will not be described in detail here.
[0078] The quantum circuit diagram in this embodiment is as follows Figure 3 As shown, a single solid line represents quantum communication and a double solid line represents classical information communication.
[0079] S2, build quantum physics system:
[0080] The prepared quantum entangled state needs to be distributed to the communicating parties to entangle with the target quantum particles, so that all entangled particles owned by each communicating party can together constitute the selected quantum physical system.
[0081] Specifically, the prepared seven-qubit entangled state The corresponding seven particles are respectively distributed in the two communication nodes controlled by Alexis and Billy in the quantum network. The quantum bit particles distributed in the Alexis network node are (1, 2, 6), and the quantum bit particles distributed in the Billy network node are (3, 4, 5, 7). The two target quantum states controlled by Alexis and Billy and the quantum channel constitute a complete quantum physics system. The quantum state of the entire system can be expressed as
[0082]
[0083] S3, target quantum particle information processing:
[0084] The communicating parties Alexis and Billy perform CNOT operations on their respective quantum bit pairs (A1, A2), (A1, A3) and (B1, B2), namely Figure 3 middle A1 and B1 are used as control qubits, and A2, A3 and B2 are used as target qubits. The three CNOT operations by Alexis and Billy make the quantum state of the whole system evolve to
[0085]
[0086] in,
[0087]
[0088] After these three controlled NOT gates, the quantum information is concentrated, and the information of the original three quanta of Alexis is concentrated on one quantum A1, and the information of B2 of Billy is concentrated on B1, while the quantum bits A2, A3 and B2 are separated from the entangled state of the initial quantum system. The remaining quantum bits form a new quantum physical system, and its quantum state is actually
[0089] S4, the two communicating parties Alexis and Billy respectively perform Bell state measurements on their respective quantum bit pairs (A1, 1) and (B1, 4), namely Figure 3 In and Operation. The four mutually orthogonal Bell states that constitute the Bell state measurement basis can be expressed as
[0090]
[0091] In the framework of the Bell state measurement basis, the remaining quantum system quantum state It can be expressed as
[0092]
[0093] It should be understood that the Bell state measurement of Alexis and Billy causes the remaining qubits 2, 3, 5, 6, and 7 to collapse into two entangled states, one being a two-qubit entangled state consisting of qubits 2 and 6, and the other being a three-qubit entangled state consisting of qubits 3, 5, and 7. The third column in Table 1 below shows the specific forms of the corresponding collapsed states of the remaining qubits under various measurement results of Alexis and Billy.
[0094] Among them, A's MR: Alexis's Bell state measurement result; B's MR: Billy's Bell state measurement result; CS: the collapsed state of the remaining quantum bit system (2, 3, 5, 6 and 7); A's RO: Alexis's recovery operation; B's RO: Billy's recovery operation.
[0095] Table 1: Correspondence between various conditions of quantum physics system after Bell state measurement
[0096]
[0097] S5, the two communicating parties Alexis and Billy reached an agreement in advance, the corresponding relationship between the Bell state measurement results and the classical information is
[0098]
[0099] According to the correspondence between Bell state measurement results and classical information, the Bell state basis measurement results are converted into 2-bit classical information and the respective measurement results are announced to each other through the classical channel, that is, Figure 3 The double solid line part.
[0100] S6, after receiving the classical information, the communicating parties Alexis and Billy determine the specific collapsed state of the remaining quantum bits (2,3,5,6,7) based on the measurement results sent by the other party. Next, Alexis and Billy choose the appropriate recovery operation and Act on the quantum bit groups (2,6) and (3,5,7) respectively. and They are composed of two and three single-qubit unitary operations, respectively, which are selected from the operation set {I,σ x ,iσ y ,σ z The fourth and fifth columns in Table 1 above show the specific forms of the recovery operations of Alexis and Billy under various measurement results.
[0101] Through the above steps, the first communication party Alexis successfully transmits its three-qubit target entangled state |ξ> to the second communication party Billy. At the same time, the second communication party Billy transmits its two-qubit target entangled state |χ> to the first communication party Alexis. And Alexis and Billy are both senders and receivers, and the amount of quantum information sent to each other is unequal. Therefore, the method proposed by the present invention exhibits bidirectional and asymmetric characteristics.
[0102] Below, we highlight the advantages of the present invention in terms of classical and quantum resource consumption, communication transmission efficiency, and measurement difficulty.
[0103] (1) Transmission efficiency. The formula for calculating the communication transmission efficiency in this embodiment is as follows:
[0104]
[0105] In the formula, q u represents the number of entangled quantum bits used as quantum channels; b t and q s Respectively represent the amount of information bits transmitted in the classical channel and the number of bits of the target quantum state to be transmitted. In this embodiment, the quantum channel is constructed by a seven-qubit entangled state, and a total of five qubits of the target entangled state are transmitted, so q s and q u 5 and 7 respectively. In order to exchange Bell state measurement results, the first communication party Alexis and the second communication party Billy sent two bits of classical information to each other. Therefore, the b of our scheme is t is equal to 4. Therefore, the transmission efficiency of the method proposed by the present invention is
[0106]
[0107] (2) Success probability. The formula for calculating the communication success probability in this embodiment is as follows:
[0108]
[0109] Where N s N represents the number of all possible measurement results made by the sender of the information; u Indicates the number of measurement results that are useful for completing the quantum task. In this example, Alexis and Billy have a total of 16 possible measurement results, each of which is helpful in reconstructing the target quantum state. Therefore, the success probability of this example is
[0110]
[0111] (3) Difficulty of implementation. The present invention only needs to perform two Bell state measurements and some simple necessary quantum operations, and does not involve the measurement of multi-qubit entangled states of three qubits or more, which greatly reduces the measurement difficulty of the present invention.
[0112] As shown in Table 2, from the perspective of technical implementation, the method of the present invention is compared with two bidirectional quantum teleportation theoretical methods in the prior art.
[0113] Among them, Scheme 1: Quantum Inf. Process. 21, 44 (2022);
[0114] Scheme 2: Int. J. Theor. Phys. 61, 187 (2022).
[0115] In the table, BSM represents Bell state measurement; GHZ3 represents three-qubit GHZ state measurement.
[0116] Table 2: Comparison of core parameters of different quantum teleportation methods
[0117]
[0118] It should be understood that, at present, the three-qubit GHZ state measurement is difficult, while the Bell state measurement is easy to achieve. It can be clearly seen from Table 2 above that the present invention has an absolute advantage in terms of both measurement difficulty and transmission efficiency.
[0119] In summary, the present invention provides an asymmetric seven-qubit entangled state with large information capacity, high transmission efficiency, strong experimental feasibility, good compatibility, simple operation and easy implementation. Bidirectional quantum teleportation method.
[0120] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.
[0121] The present invention is not limited to the above-mentioned specific implementation modes. Various changes made by ordinary technicians in this field based on the above-mentioned concepts without creative work are all within the protection scope of the present invention.
Claims
1. An asymmetric method based on seven-quantum entangled states Bidirectional quantum teleportation method, It is characterized in that The steps include: S1, transform the initial seven single-qubit pure states through logic gates to prepare a seven-qubit entangled state; S2, respectively populating the seven quantum bit particles in the seven-qubit entangled state to the first communication party and the second communication party, constructing a quantum physical system for quantum state transmission; the target quantum particle of the quantum state to be transmitted by the communication party and the prepared quantum particle obtained by the population together constitute the entangled particle owned by the communication party; S3, the first communication party and the second communication party respectively perform CNOT operations on their respective target quantum particles; S4, performing Bell state basis measurement on the entangled particles owned by the first communication party and the second communication party respectively to obtain a first measurement result and a second measurement result; S5, the first communication party and the second communication party transmit the first measurement result and the second measurement result to the other communication party respectively through a classical channel; S6, based on the received second measurement result and the first measurement result, the first communication party and the second communication party respectively perform recovery operations to reconstruct the target quantum state transmitted by the other communication party.
2. The asymmetric method based on the seven-quantum entangled state according to claim 1 Bidirectional quantum teleportation method, It is characterized in that The steps for preparing the seven-qubit entangled state in step S1 are specifically as follows: S11, seven single quantum bits with initial state |0> are combined into a seven-qubit direct product state S12, yes The middle qubits 1 and 2 perform a single-qubit Hadamard gate operation; S13, perform CNOT operation on quantum bits (1,3), (1,5), (1,7), (2,4) and (2,6) to obtain a seven-qubit entangled state Among them, quantum bits 1 and 2 are control quantum bits, and quantum bits 3, 5, 7, 4, and 6 are target quantum bits.
3. The asymmetric method based on seven quantum entangled states according to claim 2 Bidirectional quantum teleportation method, It is characterized in that The specific form of the Hadamard gate operation is: After performing the Hadamard gate operation, we get: The specific form of the CNOT operation is: Among them, m and n represent quantum bits, I = |0><0|+|1><1| is a unit operation, σ x =|0><1|+|1><0| is a Pauli operation; The seven-qubit entangled state for:
4. The asymmetric method based on seven quantum entangled states according to claim 3 Bidirectional quantum teleportation method, It is characterized in that The step S2 of respectively populating the seven quantum bit particles in the seven quantum bit entangled state to the first communication party and the second communication party is specifically as follows: The quantum bit particles (1, 2, 6) are distributed in the network nodes at the first communication party, and the quantum bit particles (3, 4, 5, 7) are distributed in the network nodes at the second communication party.
5. The asymmetric method based on seven quantum entangled states according to claim 1 Bidirectional quantum teleportation method, It is characterized in that The first target quantum state to be transmitted by the first communication party to the second communication party is an arbitrary three-qubit GHZ state, which is composed of a target quantum particle (A 1 ,A 2 ,A 3 )constitute; The second target quantum state to be transmitted by the second communication party to the first communication party is an arbitrary two-qubit Bell state, which is composed of a target quantum particle (B 1 ,B 2 )constitute.
6. The asymmetric method based on seven quantum entangled states according to claim 5 Bidirectional quantum teleportation method, It is characterized in that The step S3 specifically includes: The first communication party sends a quantum bit pair (A 1 ,A 2 ), (A 1 ,A 3 ) performs a CNOT operation, where A 1 As the control qubit, A 2 , A 3 is the target qubit; The second communication party sends a quantum bit pair (B 1 ,B 2 ) performs a CNOT operation, where B 1 As the control qubit, B 2 is the target quantum bit.
7. The asymmetric method based on seven quantum entangled states according to claim 1 Bidirectional quantum teleportation method, It is characterized in that The step S4 specifically includes: Selecting a target quantum particle and a prepared quantum particle from the entangled particles owned by the first communicating party to form a first entangled particle pair, and performing Bell state basis measurement on the first entangled particle pair to obtain a first measurement result; A target quantum particle and a prepared quantum particle are selected from the entangled particles owned by the second communicating party to form a second entangled particle pair, and a Bell state basis measurement is performed on the second entangled particle pair to obtain a second measurement result.
8. The asymmetric method based on seven quantum entangled states according to claim 7. Bidirectional quantum teleportation method, It is characterized in that The Bell state basis measurement basis vectors in step S4 are composed of four mutually orthogonal Bell states, which are:
9. The asymmetric method based on seven quantum entangled states according to claim 8 Bidirectional quantum teleportation method, It is characterized in that The step S5 specifically includes: converting the Bell state basis measurement result into 2-bit classical information according to the correspondence between the Bell state measurement result and the classical information and transmitting the information through the classical channel; The corresponding relationship between the Bell state measurement result and the classical information is:
10. The asymmetric method based on seven quantum entangled states according to claim 6 Bidirectional quantum teleportation method, It is characterized in that The step S6 specifically includes: Perform two single-qubit unitary operations according to the received second measurement result and the prepared quantum particles of the first communication party that have not undergone Bell basis measurement, to reconstruct a second target quantum state transmitted by the second communication party; Perform three single-qubit unitary operations according to the received first measurement result and the prepared quantum particles of the second communication party that have not undergone Bell basis measurement, to reconstruct the first target quantum state transmitted by the first communication party; The single-qubit unitary operation is selected from the set of operations {I,σ x ,iσ y ,σ z }, Where I=|0><0|+|1><1| is a unit operation, σ x =|0><1|+|1><0| is the Pauli operation, iσ y =|0><1|-|1><0| is the Pauli operation, σ z =|0><0|-|1><1| is the Pauli operation.