This paper presents a new bidirectional quantum teleportation (BQT) protocol in which users can simultaneously transmit an arbitrary number of particles to each other via a four-qubit cluster state as quantum channel. With the use of auxiliary qubits and controlled-not gates, transformation circuits are introduced which transform n -qubit states into single superposition state and then teleport them over the channel by using Bell-state measurement and applying a proper Pauli operator. At last, with the aid of another transformation circuit, the initial states can be reconstructed. With this method, the BQT purpose is realized more advantageous compared to recent presented protocols.

中文翻译：

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使用四个量子位簇状态的任意数量量子位的双向量子隐形传态

本文提出了一种新的双向量子隐形传态 (BQT) 协议，在该协议中，用户可以通过作为量子通道的四量子位簇状态同时传输任意数量的粒子。通过使用辅助量子位和受控非门，引入了转换电路，将 n 个量子位状态转换为单个叠加态，然后通过使用贝尔状态测量和应用适当的泡利算子将它们传送到通道上。最后，借助另一个变换电路，可以重建初始状态。使用这种方法，与最近提出的协议相比，实现 BQT 的目的更加有利。