论文标题
嘈杂量子状态的信息可回收性
Information recoverability of noisy quantum states
论文作者
论文摘要
从量子系统中提取经典信息是许多量子算法的重要步骤。但是，由于系统容易出现量子声，并且在量子动态下的失真尚未得到充分研究，因此可能会损坏此信息。在这项工作中，我们介绍了一个系统的框架，以研究我们如何从嘈杂的量子状态中检索信息的能力。给定一个嘈杂的量子通道，我们充分表征了可回收的经典信息的范围。这种情况允许自然措施量化通道的信息可恢复性。此外，我们解决了最低信息检索成本，该成本与相应的最佳协议可以通过半决赛编程有效地计算。作为应用程序，我们建立了实用量子噪声的信息检索成本的限制，并采用相应的协议来减轻基础状态能量估计中的错误。我们的工作给出了从可回收范围到回收成本的嘈杂量子状态的信息可回收性的第一个完整表征，从而揭示了取消概率误差的最终限制。
Extracting classical information from quantum systems is an essential step of many quantum algorithms. However, this information could be corrupted as the systems are prone to quantum noises, and its distortion under quantum dynamics has not been adequately investigated. In this work, we introduce a systematic framework to study how well we can retrieve information from noisy quantum states. Given a noisy quantum channel, we fully characterize the range of recoverable classical information. This condition allows a natural measure quantifying the information recoverability of a channel. Moreover, we resolve the minimum information retrieving cost, which, along with the corresponding optimal protocol, is efficiently computable by semidefinite programming. As applications, we establish the limits on the information retrieving cost for practical quantum noises and employ the corresponding protocols to mitigate errors in ground state energy estimation. Our work gives the first full characterization of information recoverability of noisy quantum states from the recoverable range to the recovering cost, revealing the ultimate limit of probabilistic error cancellation.
