CN114401088A - Quantum secret sharing method based on super-entanglement assistance - Google Patents

Abstract

A quantum secret sharing method based on super-entanglement assistance is characterized in that a user 1 prepares a super-entangled three-photon GHZ state and selects a security detection photon pair. User 1 sends two photons in all super-entangled GHZ states to user 2 and user 3. After receiving the photons, user 1 publishes the location and measurement base for security detection photons; and (3) carrying out coding operation on the non-safety detected photon pair, the user 2 and the user 3, and carrying out complete GHZ state analysis of polarization freedom by the three-party user. The user 1 obtains the encoded polarization GHZ state to obtain an original key; for the photon pair for safety detection, the three users use the measuring base to measure the photons in the hands of the three users, the safety detection is carried out, and if the photons pass through the measuring base, the three users carry out error correction and secret amplification on the original secret key to form a final safety secret key. In the method, the complete distinction of eight polarization GHZ states is realized without base processing, each super-entangled GHZ state can transmit a 3-bit key, the key generation efficiency is obviously improved, and the practicability is improved.

Description

A Superentanglement-Assisted Quantum Secret Sharing Method

technical field

The invention belongs to the technical field of quantum communication, in particular to a quantum secret sharing method based on super-entanglement assistance.

Background technique

Quantum communication is a way of transmitting information using the basic principles of quantum mechanics. The security of quantum communication is based on the fundamental principles of quantum mechanics, including the no-cloning theorem, the nonlocality of entanglement, etc. Any eavesdropper's eavesdropping behavior will destroy the state of the sent particles, which will be discovered by the communicating parties. Therefore, quantum communication has absolute security, which is the biggest advantage of quantum communication different from classical communication.

Quantum cryptography is an important branch of quantum communication, mainly including quantum key distribution (QKD), quantum secret sharing (QSS) and so on. QKD refers to the use of entangled channels to distribute security keys between two users. And QSS means that the secret sender splits the secret information into several parts of the password, and distributes it to multiple proxy members by using the quantum state as the carrier; only the proxy members can cooperate to recover the secret. Similarly, QSS also allows multiple proxy members to jointly deliver keys to the receiver through cooperation. Like QKD, QSS has unconditional security in theory and has important application value in national defense, finance, etc. The original QSS scheme needs to distribute the GHZ state among the three communicating parties, and the three communicating parties randomly choose the right-angle basis or the diagonal basis to measure the photons in their hands. Only when the measurement bases selected by the three parties are the same, the key transfer can be realized, and the traditional GHZ state analysis can only distinguish 2 of the 8 GHZ states. The above two points lead to a low key generation rate of the original QSS.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies in the prior art, and to provide a quantum secret sharing method based on super-entanglement assistance, in which the user 2 and the user 3 cooperate to jointly deliver the key to the user 1. This method does not require three communication parties to perform base-to-base processing, and can fully distinguish eight GHZ states by using linear optics, which can significantly improve the security key generation rate of QSS, and this method can be fully realized under the current experimental conditions.

A quantum secret sharing method based on superentanglement assistance, comprising the following steps:

Step 1, User 1 uses a superentangled source to prepare a large number of identical polarized P-momentum M superentangled three-photon GHZ states for quantum communication; User 1 splits each superentangled photon pair into three photon sequences, respectively Named as sequence 1, 2, 3; meanwhile, user 1 randomly selects the three-photon GHZ state as the security detection photon pair;

Step 2: User 1 sends the photons of sequence 2 and sequence 3 to user 2 and user 3 respectively. After user 2 and user 3 receive the photons, they notify user 1 through classical communication, and user 1 announces the location of each security detection photon pair. sum and publish a measurement basis in two degrees of freedom, the measurement basis is randomly selected from a right angle basis and a diagonal basis;

Step 3: For the non-safety detection photons in sequence 2 and sequence 3, user 2 and user 3 randomly use unitary operations on four polarization degrees of freedom, respectively, and perform encoding operations on the polarization degrees of freedom to load the encryption. key, and do nothing on the momentum degrees of freedom;

Step 4: After the encoding is completed, user 1, user 2 and user 3 use the momentum degree of freedom entanglement as an aid to perform a complete GHZ state analysis of the polarization degree of freedom for the encoded three-photon pair; user 2 and user 3 publish their respective detector responses In this case, user 1 knows the encoded GHZ state based on his own detector response, so as to obtain the key jointly transmitted by user 2 and user 3;

Step 5, for the security detection photon pair, user 1, user 2 and user 3 measure the two degrees of freedom of polarization and momentum according to the measurement base published by user 1 and publish the measurement results; in any degree of freedom, If the measurement base is a right-angle basis, the measurement results of the three parties are used to estimate the bit error rate of the photon transmission process; if the measurement base is a diagonal base, the three-party measurement results are used to estimate the phase error rate of the photon transmission process; The sum is defined as the total error rate on this degree of freedom; if the total error rate of the security detection photon in any degree of freedom exceeds the set threshold, it proves that the photon transmission process is not secure, the communication is terminated, and the three users discard the original key; if If the total error rate of both degrees of freedom is lower than the set threshold, it proves that the photon transmission process is safe, and proceed to the next step;

Step 6: User 1, User 2 and User 3 perform error correction and private amplification on the open channel to form a final security key.

其中，|ψ₁ ⁺>_P属于8个极化GHZ态之一，在Z基和X基下8个极化GHZ态的表达式分别为：Further, the user 1 uses a superentanglement source to prepare a polarization-momentum superentangled GHZ state

Among them, |ψ ₁ ⁺ > _P belongs to one of the 8 polarized GHZ states, and the expressions of the 8 polarized GHZ states in the Z base and the X base are:

下标1、2、3分别代表光子所在的序列号；|H>, |V> are the fundamental vectors of the Z base, representing the horizontal polarization and vertical polarization of the photon, respectively, |±> _P is the fundamental vector of the X base,

The subscripts 1, 2, and 3 represent the serial numbers of the photons, respectively;

|ψ ₁ ⁺ > _M belongs to the 8 GHZ states of the momentum degree of freedom, and the 8 momentum GHZ states under the Z basis and the X basis are in the form:

下标1、2、3分别代表光子所在的序列号。Among them, |L>, |R> are the basis vectors of the Z basis, representing the left and right of the momentum, respectively, and |±> _M are the basis vectors of the diagonal basis, satisfying

The subscripts 1, 2, and 3 represent the serial numbers of the photons, respectively.

Further, in step 3, for the non-safety detection superentangled GHZ photon pair shared by three parties, user 2 and user 3 do not perform any operation on the momentum degree of freedom, but perform an encoding operation on the polarization degree of freedom, and the polarization The four encoding operations on degrees of freedom include:

After the encoding is completed, the polarized GHZ state shared by the three-party users evolves into one of |ψ _i ^± > _P (i=1, 2, 3, 4); the three-party users agree in advance |ψ ₁ ⁺ > _P , |ψ ₁ ^- > _P , |ψ ₂ ⁺ > _P , |ψ ₂ ^- > _P , |ψ ₃ ⁺ > _P , |ψ ₃ ^- > _P , |ψ ₄ ⁺ > _P , |ψ ₄ ^- > _P represent 000, 001, and 010, respectively , 011, 100, 101, 110, 111 these 8 codes.

用户2：

用户3：

每种GHZ态等概率地对应8种不同的探测器响应情况；用户2和用户3公布其位置处的单光子探测器响应情况，用户1结合自己的探测器响应情况推测出编码后的GHZ态

由此推测出用户2和用户3联合传递的原始密钥。Further, in step 4, user 1, user 2, and user 3 realize complete GHZ state analysis of polarization degrees of freedom through momentum entanglement assistance, that is, 8 polarization GHZ states can be completely distinguished; each of the three users has 4 single GHZ states. Photon detectors, respectively User 1:

User 2:

User 3:

Each GHZ state corresponds to 8 different detector response situations with equal probability; user 2 and user 3 announce the response situation of single-photon detectors at their positions, and user 1 infers the encoded GHZ state based on his own detector response situation

From this, the original key jointly transmitted by user 2 and user 3 is deduced.

Further, in step 5, the security detection includes:

User 1 publishes the position and measurement base of the safety detection photon pair, and then three users randomly select Z base or X base to measure the safety detection photon in the pair and publish the measurement result. In the polarization and momentum degrees of freedom, if the measurement base is a right-angle basis, the three-way measurement results are used to estimate the bit error rate Q _Pb (Q _Mb ) of the photon transmission process, and Q _Pb (Q _Mb ) is equal to the three-way measurement results are not all the same Probability; if the measurement basis is a diagonal basis, the three-way measurement results are used to estimate the phase error rate Q _Pp (Q _Mp ) of the photon transmission process, and Q _Pp (Q _Mp ) is equal to the three-way measurement results. There are an even number of |+> _P( The probability of _M) ; the sum of the two error rates is defined as the total error rate on this degree of freedom Q _Pt = Q _Pb + Q _Pp (Q _Mt = Q _Mb + Q _Mp ); if Q _Pt or Q _Mt is higher than the set If the threshold value is , it means that the photon transmission process is not secure, then discard the original key generated and check the channel again; when the total error rates Q _Pt and Q _Mt of the two degrees of freedom are both lower than the set threshold, it means that the communication is secure.

Further, in this method, the initial quantum state of the superentangled photons and the detector responses of user 2 and user 3 after encoding are public information, the detector response of user 1 is not public, and the three parties after user 2 and user 3 complete the encoding. The shared polarized GHZ state is known only to user 1.

Further, the security key generation rate R _sec of this method is expressed as:

R _sec =R _sift [1-(1+f)H(Q _t )]

Among them, Q _t represents the total error rate of the key, R _sift represents the screening key generation rate, f is the error correction efficiency of post-processing, take f=1.16, and H(x) is the binary Shannon entropy:

H(x)=-x log ₂ (x)-(1-x)log ₂ (1-x).

The total error rate of the key is Q _t =(1-Q _Pt )(1-Q _Mt ).

Compared with the prior art, the beneficial effects achieved by the present invention include:

(1) This method pre-prepares GHZ state superentangled photon pairs for quantum communication, and user 1 sends two photons in each GHZ state photon pair to user 2 and user 3, respectively. After the photons are distributed, security detection is adopted, so that the eavesdropper cannot intercept the photons without being discovered, thus theoretically eliminating key leakage and ensuring the security of the key transmission process.

(2) This method uses the polarization-momentum super-entangled GHZ state and uses the momentum entanglement to assist to realize the complete analysis of the polarization GHZ state, so that the three-party user can generate the key without performing the base operation. Since the polarization GHZ state analysis scheme can completely distinguish 8 polarization GHZ states, in theory, each pair of superentangled GHZ states can transmit a 3-bit key, which can significantly improve the key transmission efficiency of QSS.

(3) All equipment used in this method is based on linear optics, which can be realized under the existing experimental conditions, which improves the practicability of the scheme.

Description of drawings

FIG. 1 is a flowchart of a method for quantum secret sharing based on superentanglement assistance in an embodiment of the present invention.

代表12个单光子探测器。2 is an analysis diagram of a superentangled GHZ state based on a quantum secret sharing method assisted by superentanglement in an embodiment of the present invention, wherein PBS represents a polarized beam splitter, which can completely transmit H-polarized photons and completely reflect V-polarized photons. transformed photons. HWP stands for half-wave plate and can achieve

Represents 12 single-photon detectors.

3 is a schematic block diagram of a quantum secret sharing method based on super-entanglement assistance in an embodiment of the present invention; Encode represents the encoders of user 2 and user 3, and can perform four encoding operations on photons in terms of polarization degrees of freedom.

FIG. 4 is a graph showing the correspondence between the detector response and the polarized GHZ state of a superentanglement-assisted quantum secret sharing method according to an embodiment of the present invention.

Detailed ways

The technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings.

As shown in FIG. 1, an embodiment of the present invention provides a quantum secret sharing method based on superentanglement assistance, including:

其中，|ψ₁ ⁺>_P属于8个极化GHZ态之一，在Z基和X基下，8个极化GHZ态的表达式分别为：Step 1: User 1 uses a superentangled source to prepare a large number of identical polarization (P)-momentum (M) superentangled three-photon GHZ states for quantum communication. User 1 splits each superentangled photon pair into three photon sequences, named sequences 1, 2, and 3, respectively. The superentangled three-photon GHZ state has the form

Among them, |ψ ₁ ⁺ > _P belongs to one of the eight polarized GHZ states, and under the Z base and the X base, the expressions of the eight polarized GHZ states are:

下标1，2，3分别代表光子所在的序列号。|H>, |V> are the fundamental vectors of the Z base, representing the horizontal polarization and vertical polarization of the photon, respectively, |±> _P is the fundamental vector of the X base,

The subscripts 1, 2, and 3 represent the serial numbers of the photons, respectively.

Similarly, |ψ ₁ ⁺ > _M belongs to the 8 GHZ states of the momentum degree of freedom. Under the Z basis and the X basis, the 8 momentum GHZ states are in the form of:

下标1，2，3分别代表光子所在的序列号。Among them, |L>, |R> are the basis vectors of the Z basis, representing the left and right of the momentum, respectively, and |±> _M are the basis vectors of the diagonal basis, satisfying

The subscripts 1, 2, and 3 represent the serial numbers of the photons, respectively.

At the same time, user 1 randomly selects enough three-photon GHZ states as pairs of safe detection photons. User 1 sends the photons of sequence 2 and sequence 3 to user 2 and user 3 respectively. After user 2 and user 3 receive the photons, they inform user 1, and user 1 announces the position of the safety detection photon pair and the measurement of the two degrees of freedom base (randomly chosen from right-angled and diagonal bases).

For the non-safety detection of superentangled GHZ photon pairs shared by three parties, user 2 and user 3 do nothing in the momentum degree of freedom, but encode in the polarization degree of freedom. The four encoding operations on the polarization degrees of freedom include:

用户3的操作为

极化自由度上的GHZ态将演化为

三个用户约定好|ψ₁ ⁺>_P，|ψ₁ ^->_P，|ψ₂ ⁺>_P，|ψ₂ ^->_P，|ψ₃ ⁺>_P，|ψ₃ ^->_P，|ψ₄ ⁺>_P，|ψ₄ ^->_P分别代表000，001，010，011，100，101，110，111这8种编码(原始密钥)。The above operations can make the GHZ state |ψ ₁ ⁺ > _P in the polarization degree of freedom evolve into the above-mentioned eight polarization GHZ states. For example, if user 2's action is

User 3's action is

The GHZ state in the polarization degrees of freedom will evolve into

The three users agree on |ψ ₁ ⁺ > _P , |ψ ₁ ^- > _P , |ψ ₂ ⁺ > _P , |ψ ₂ ^- > _P , |ψ ₃ ⁺ > _P , |ψ ₃ ^- > _P , |ψ ₄ ⁺ > _P , |ψ ₄ ^- > _P represent 8 codes (original keys) of 000, 001, 010, 011, 100, 101, 110, and 111, respectively.

用户2：

用户3：

每种极化GHZ态等概率地对应8种不同的探测器响应情况，具体的8种极化GHZ态对应的探测器响应情况如图4所示。After the coding is completed, user 1, user 2, and user 3 use momentum entanglement to assist in realizing the complete GHZ state analysis of the polarization degree of freedom, that is, the eight polarization GHZ states can be completely distinguished. There are 4 single-photon detectors at each of the three users, user 1:

User 2:

User 3:

Each polarization GHZ state corresponds to eight different detector response situations with equal probability, and the specific detector response situations corresponding to the eight polarization GHZ states are shown in Fig. 4 .

由此得到用户2和用户3联合传递的密钥。例如，若用户2的操作为

用户3的操作为

如编码后的极化GHZ态为|ψ₄ ^->_P，用户1可得到用户2和用户3联合传递的密钥为111，若用户2的操作为

用户3的操作为

如编码后的极化GHZ态为

用户1可得到用户2和用户3联合传递的密钥为011。After the measurement is completed, user 2 and user 3 announce the response of the single-photon detector at their location, and user 1 infers the encoded super-entangled GHZ state according to the three-party detector response.

Thus, the key jointly transmitted by user 2 and user 3 is obtained. For example, if user 2's action is

User 3's action is

If the encoded polarized GHZ state is |ψ ₄ ^- > _P , user 1 can obtain the key jointly transmitted by user 2 and user 3 as 111. If user 2 operates as

User 3's action is

For example, the encoded polarized GHZ state is

User 1 can obtain the key jointly transmitted by User 2 and User 3 as 011.

To ensure the security of the key transmission process, the three users need to perform security detection. For the safety detection photon pair, user 1, user 2 and user 3 measure the two degrees of freedom of polarization and momentum according to the published measurement base, and publish the measurement results. In any degree of freedom, if the right-angle basis is selected, the three-party measurement results can be used to estimate the bit error rate of the photon transmission process; if the diagonal basis is selected, the three-party measurement results can be used to estimate the phase error rate of the photon transmission process. The sum of the two error rates is defined as the total error rate on that degree of freedom. If the total error rate of the security detection photon in any degree of freedom exceeds the set threshold, it proves that the photon transmission process is not secure, the communication is terminated, and the three users discard the original key; if the total error rate of the two degrees of freedom is lower than the set threshold If the threshold is set, it proves that the photon transmission process is safe, and the three users keep the original key.

Finally, user 1, user 2 and user 3 perform error correction and private amplification on the open channel to form the final security key.

It should be noted that the eavesdropper cannot obtain information during the communication process. In the transmission process of user 1 sending photons to user 2 and user 3, no encoding operation is performed at this time, so the transmitted photons do not contain key information, that is, eavesdroppers cannot obtain any information. After coding, only user 2 and user 3 publish the measurement results, and user 1 does not publish the measurement results, so the eavesdropper cannot obtain the coded GHZ state information, which can ensure the security of the whole scheme.

As will be appreciated by those skilled in the art, the embodiments of the present application may be provided as a method, a system, or a computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The above descriptions are only the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, but any equivalent modifications or changes made by those of ordinary skill in the art based on the contents disclosed in the present invention should be included in the within the scope of protection described in the claims.

Claims (7)

1. a quantum secret sharing method based on superentanglement assistance, is characterized in that: comprise the steps: Step 1, User 1 uses a superentangled source to prepare a large number of identical polarized P-momentum M superentangled three-photon GHZ states for quantum communication; User 1 splits each superentangled photon pair into three photon sequences, respectively Named as sequence 1, 2, 3; meanwhile, user 1 randomly selects the three-photon GHZ state as the security detection photon pair; Step 2: User 1 sends the photons of sequence 2 and sequence 3 to user 2 and user 3 respectively. After user 2 and user 3 receive the photons, they notify user 1 through classical communication, and user 1 announces the location of each security detection photon pair. sum and publish a measurement basis in two degrees of freedom, the measurement basis is randomly selected from a right angle basis and a diagonal basis; Step 3: For the non-safety detection photons in sequence 2 and sequence 3, user 2 and user 3 randomly use unitary operations on four polarization degrees of freedom, respectively, and perform encoding operations on the polarization degrees of freedom to load the encryption. key, and do nothing on the momentum degrees of freedom; Step 4: After the encoding is completed, user 1, user 2 and user 3 use the momentum degree of freedom entanglement as an aid to perform a complete GHZ state analysis of the polarization degree of freedom for the encoded three-photon pair; user 2 and user 3 publish their respective detector responses In this case, user 1 knows the encoded GHZ state based on his own detector response, so as to obtain the key jointly transmitted by user 2 and user 3; Step 5, for the security detection photon pair, user 1, user 2 and user 3 measure the two degrees of freedom of polarization and momentum according to the measurement base published by user 1 and publish the measurement results; in any degree of freedom, If the measurement base is a right-angle basis, the three-way measurement results are used to estimate the bit error rate of the photon transmission process; if the measurement base is a diagonal base, the three-way measurement results are used to estimate the phase error rate of the photon transmission process; The sum is defined as the total error rate on this degree of freedom; if the total error rate of the security detection photon in any degree of freedom exceeds the set threshold, it proves that the photon transmission process is not secure, the communication is terminated, and the three users discard the original key; if If the total error rate of both degrees of freedom is lower than the set threshold, it proves that the photon transmission process is safe, and proceed to the next step; Step 6: User 1, User 2 and User 3 perform error correction and private amplification on the open channel to form a final security key. 2. A kind of quantum secret sharing method based on superentanglement assistance according to claim 1, is characterized in that: described user 1 uses superentanglement source to prepare polarization-momentum superentanglement GHZ state

Among them, |ψ ₁ ⁺ > _P belongs to one of the eight polarized GHZ states, and the expressions of the eight polarized GHZ states in the Z-base and the X-base are:

|H>, |V> are the fundamental vectors of the Z base, representing the horizontal polarization and vertical polarization of the photon, respectively, |±>P is the fundamental vector of the X base,

The subscripts 1, 2, and 3 represent the serial numbers of the photons, respectively; |ψ ₁ ⁺ > _M belongs to the 8 GHZ states of the momentum degree of freedom, and the 8 momentum GHZ states under the Z basis and the X basis are in the form:

Among them, |L>, |R> are the basis vectors of the Z basis, representing the left and right sides of the momentum, respectively, and |±> _M are the basis vectors of the diagonal basis, satisfying

The subscripts 1, 2, and 3 represent the serial numbers of the photons, respectively. 3. a kind of quantum secret sharing method based on superentanglement assistance according to claim 1, is characterized in that: in step 3, for the non-safety detection superentanglement GHZ photon pair shared by three parties, user 2 and user 3 are paired photons No operation is performed on the momentum degree of freedom, but the encoding operation is performed on the polarization degree of freedom. The four encoding operations on the polarization degree of freedom include:

After the coding is completed, the polarized GHZ state shared by the three-party users evolves into one of |ψ _i ^± > _P (i=1, 2, 3, 4); the three-party users agree in advance |ψ ₁ ⁺ > _P , |ψ ₁ ^- > _P , |ψ ₂ ⁺ > _P , |ψ ₂ ^- > _P , |ψ ₃ ⁺ > _P , |ψ ₃ ^- > _P , |ψ ₄ ⁺ > _P , |ψ ₄ ^- > _P represent 000, 001, and 010, respectively , 011, 100, 101, 110, 111 these 8 codes. 4. a kind of quantum secret sharing method based on super-entanglement assistance according to claim 1, is characterized in that: in step 4, user 1, user 2, user 3 realize the complete GHZ state of polarization degree of freedom through momentum entanglement assistance Analysis, that is, the 8 polarized GHZ states can be completely distinguished; there are 4 single-photon detectors at each of the three users, which are user 1:

User 2:

User 3:

Each GHZ state corresponds to 8 different detector response situations with equal probability; user 2 and user 3 announce the response situation of the single-photon detector at their location, and user 1 infers the encoded GHZ state based on his own detector response situation

From this, the original key jointly transmitted by user 2 and user 3 is deduced. 5. a kind of quantum secret sharing method based on superentanglement assistance according to claim 1, is characterized in that: in step 5, the security detection comprises: User 1 publishes the position and measurement base of the safety detection photon pair, and then three users randomly select Z base or X base to measure the safety detection photon in the pair and publish the measurement result. In the polarization and momentum degrees of freedom, if the measurement base is a right-angle basis, the three-way measurement results are used to estimate the bit error rate Q _Pb (Q _Mb ) of the photon transmission process, and Q _Pb (Q _Mb ) is equal to the three-way measurement results are not all the same Probability; if the measurement basis is a diagonal basis, the three-way measurement results are used to estimate the phase error rate Q _Pp (Q _Mp ) of the photon transmission process, and Q _Pp (Q _Mp ) is equal to the three-way measurement results. There are an even number of |+> _P( The probability of _M) ; the sum of the two error rates is defined as the total error rate on this degree of freedom Q _Pt = Q _Pb + Q _Pp (Q _Mt = Q _Mb + Q _Mp ); if Q _Pt or Q _Mt is higher than the set If the threshold value is , it means that the photon transmission process is not secure, then discard the original key generated and check the channel again; when the total error rates Q _Pt and Q _Mt of the two degrees of freedom are both lower than the set threshold, it means that the communication is secure. 6. a kind of quantum secret sharing method based on superentanglement assistance according to claim 1, is characterized in that: in this method, the initial quantum state of superentanglement photon and the detector response situation of user 2 and user 3 after encoding are: Public information, user 1's detector response is not public, and only user 1 knows the polarization GHZ state shared by the three parties after user 2 and user 3 complete the encoding. 7. a kind of quantum secret sharing method based on superentanglement assistance according to claim 1, is characterized in that: the security key generation rate R _sec of this method is expressed as: R _sec =R _sift [1-(1+f)H(Q _t )] Among them, Q _t represents the total error rate of the key, R _sift represents the screening key generation rate, f is the error correction efficiency of post-processing, take f=1.16, and H(x) is the binary Shannon entropy: H(x)=-x log ₂ (x)-(1-x)log ₂ (1-x). The total error rate of the key is Q _t =(1-Q _Pt )(1-Q _Mt ).

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