We propose a novel scheme for faithful bidirectional quantum teleportation (BQT) in which Alice can transmit an unknown N-qubit entangled state to Bob and at the same time Bob can transmit an unknown M-qubit entangled state to Alice by using a four-qubit entangled G-state as a quantum channel. We also propose a new scheme for cyclic QT of multi-qubit entangled states by using two G-states as a quantum channel. The advantage of our schemes is that it seems to be much simpler and requires reduced number of qubits in quantum channel as compared with the other proposed schemes.

中文翻译：

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通过 G 态实现多量子位纠缠态的双向量子隐形传态和循环量子隐形传态

我们提出了一种用于忠实双向量子隐形传态 (BQT) 的新方案，其中 Alice 可以向 Bob 传输一个未知的 N-qubit 纠缠态，同时 Bob 可以使用一个四量子位向 Alice 传输一个未知的 M-qubit 纠缠态纠缠 G 态作为量子通道。我们还提出了一种新的多量子位纠缠态循环 QT 方案，使用两个 G 态作为量子通道。与其他提议的方案相比，我们的方案的优点是它似乎更简单，并且需要减少量子通道中的量子比特数。