A total of seven qubits are in a maximally entangled state. Using such an entangled state as quantum channel is based on the construction requirements of quantum long-distance communication [Pan et al., Nature 488, 185 (2012)]. Multi-party quantum channel (QC) should be studied. We put forward three deterministic bidirectional quantum controlled teleportation (BQCT) schemes. To be specific, BQCT can be realized between any two parties in a deterministic manner with another as the control. Alternatively, the BQCT capacity of such state in the given qubit distribution is thus essentially revealed by virtue of the schemes.

中文翻译：

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通过量子纠缠交换的四智能体双向量子控制隐形传态

共有七个量子位处于最大纠缠状态。使用这种纠缠态作为量子信道，是基于量子长距离通信的建设需求[潘等。,自然 488, 185 (2012)]。应该研究多方量子信道（QC）。我们提出了三种确定性双向量子控制隐形传态（BQCT）方案。具体来说，BQCT可以在任意两方之间以另一方作为控制的确定性方式实现。或者，在给定的量子比特分布中这种状态的 BQCT 容量因此基本上是通过这些方案来揭示的。