论文标题
对纠缠状态的普遍最佳验证，并进行非态度测量
Universally Optimal Verification of Entangled States with Nondemolition Measurements
论文作者
论文摘要
量子状态的有效和可靠的表征在大多数（如果不是全部）量子信息处理任务中起着至关重要的作用。在这项工作中，我们提出了一种普遍最佳的协议，用于通过采用所谓的量子非态度测量，以验证纠缠状态，以便验证效率等于最佳的全球策略。我们的协议不是作为标准验证策略作为标准验证策略而不是概率的，而是依次构建的，因此对实验实现更有利。此外，在每次测量后，目标状态保留在协议中，因此可以在任何后续任务中重复使用。我们证明了我们方案的最佳验证，任意两Q Quibent纯状态和稳定剂状态的力量。我们还证明，我们的协议能够执行任务，包括保真度估计和状态准备。
The efficient and reliable characterization of quantum states plays a vital role in most, if not all, quantum information processing tasks. In this work, we present a universally optimal protocol for verifying entangled states by employing the so-called quantum nondemolition measurements, such that the verification efficiency is equivalent to that of the optimal global strategy. Instead of being probabilistic as the standard verification strategies, our protocol is constructed sequentially, which is thus more favorable for experimental realizations. In addition, the target states are preserved in the protocol after each measurement, so can be reused in any subsequent tasks. We demonstrate the power of our protocol for the optimal verification of Bell states, arbitrary two-qubit pure states, and stabilizer states. We also prove that our protocol is able to perform tasks including fidelity estimation and state preparation.
