In this work, we consider the preservation of a measurement for quantum systems interacting with an environment. Namely, a method of preserving an optimal measurement over a channel is devised, what we call channel coding of a quantum measurement in that operations are applied before and after a channel in order to protect a measurement. A protocol that preserves a quantum measurement over an arbitrary channel is shown only with local operations and classical communication without the use of a larger Hilbert space. Therefore, the protocol is readily feasible with present day’s technologies. Channel coding of qubit measurements is presented, and it is shown that a measurement can be preserved for an arbitrary channel for both i) pairs of qubit states and ii) ensembles of equally probable states. The protocol of preserving a quantum measurement is demonstrated with IBM quantum computers.

中文翻译：

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量子测量的信道编码

在这项工作中，我们考虑保留与环境相互作用的量子系统的测量。即，设计了一种在信道上保持最佳测量的方法，我们称之为量子测量的信道编码，因为在信道之前和之后应用操作以保护测量。保留任意信道上的量子测量的协议仅在本地操作和经典通信中显示，而不使用更大的希尔伯特空间。因此，使用当今的技术，该协议很容易实现。提出了量子位测量的通道编码，并且表明对于 i) 量子位状态对和 ii) 等概率状态的集合，可以为任意通道保留测量。