噪声情况下的量子网络直接通信

提出和研究了噪声情况下的量子网络直接通信. 通信过程中所有量子节点共享多粒子Greenberger-Horne-Zeilinger (GHZ)量子纠缠态; 发送节点将手中共享的GHZ态的粒子作为控制比特、传输秘密信息的粒子作为目标比特, 应用控制非门(CNOT)操作; 每个接收节点将手中共享GHZ 态的粒子作为控制比特、接收到的秘密信息粒子作为目标比特, 再次应用CNOT门操作从而获得含误码的秘密信息. 每个接收节点从秘密信息中提取部分作为检测比特串, 并将剩余的秘密信息应用奇偶校验矩阵纠正其中存在的比特翻转错误, 所有接收节点获得纠正后的秘密信息. 对协议安全、吞吐效率、通信效率等进行了分析和讨论.

Quantum network direct communication protocol over noisy channel

The direct communication protocol of quantum network over noisy channel is proposed and investigated in this study. In communication process, all quantum nodes share multiparticle Greenberger-Horne-Zeilinger (GHZ)-states. The sending node takes the GHZ-state particle in the hand as the control qubit and the particle for sending secret information as the target qubit, which carries out the CNOT gate operation for the control and target qubit. Each receiving node takes the GHZ-state particle in the hand as the control qubit and the particle of the received secret information as the target qubit, in which the CNOT gate operation is repeated to obtain the secret information that contains the bit error. Each receiving node uses the extracted part of qubits as the checking qubits, and then corrects the bit-flip errors using parity check matrix together with the rest part of qubits. As a result, all receiving nodes obtain rectified secret information. In addition to the high security analysis, this study also presents the detailed analyses of the throughput efficiency and the communication performance.