We show that the fidelity offered by the standard teleportation protocol under noisy channels applied successively can be significantly improved, when used in conjunction with a quantum switch. In particular, we find that for two such teleportation channels conjugated with an indefinite causal order, teleportation fidelity beyond the classical threshold is achieved for significantly larger noise than would be possible conventionally. One can even make the effective teleportation channel perfectly faithful for very large noise. We also discuss the generalization of our scheme for more than two pathways, and define a figure of merit in that context.

中文翻译：

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因果顺序的叠加在非常嘈杂的信道下实现了隐形传态的量子优势

我们表明，当与量子开关结合使用时，标准隐形传态协议在连续应用的嘈杂通道下提供的保真度可以得到显着提高。特别是，我们发现，对于与不确定因果顺序共轭的两个这样的隐形传态通道，实现了超出经典阈值的隐形传态保真度，以获得比传统可能更大的噪声。甚至可以使有效的传送通道完全忠实于非常大的噪音。我们还讨论了我们的方案对两个以上途径的概括，并在这种情况下定义了一个品质因数。