Simulating all quantum measurements using only projective measurements and postselection
Simulating all quantum measurements using only projective measurements and postselection
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DOI：
10.1103/physreva.100.012351
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发表时间：
2019-07-31
影响因子：
2.9
通讯作者：
Puchala, Zbigniew
中科院分区：
文献类型：
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作者：
Oszmaniec, Michal;Maciejewski, Filip B.;Puchala, Zbigniew
我们报告了一个替代方案，用于实现广义量子测量，不需要使用辅助系统。我们的方法仅利用（a）经典随机性和后处理，（B）相关量子系统上的投影测量，以及（c）对未观察到的某些结果进行后选择。该方案以最优成功概率1/d实现了d维的任意量子测量。我们应用我们的结果来约束的相对功率的投影和广义测量明确的状态歧视。最后，我们在IBM量子处理器上进行了实验测试。有趣的是，由于纠缠门的实现中涉及的噪声，我们的方案实现广义量子比特测量的质量优于使用辅助系统的标准构造。
We report an alternative scheme for implementing generalized quantum measurements that does not require the usage of an auxiliary system. Our method utilizes solely (a) classical randomness and postprocessing, (b) projective measurements on a relevant quantum system, and (c) postselection on nonobserving certain outcomes. The scheme implements arbitrary quantum measurement in dimension d with the optimal success probability 1/d. We apply our results to bound the relative power of projective and generalized measurements for unambiguous state discrimination. Finally, we test our scheme experimentally on an IBM quantum processor. Interestingly, due to noise involved in the implementation of entangling gates, the quality with which our scheme implements generalized qubit measurements outperforms the standard construction using an auxiliary system.