论文标题
高斯行动的限制和高斯州歧视的测量及其用于国家比较的应用
Limit of Gaussian operations and measurements for Gaussian state discrimination, and its application to state comparison
论文作者
论文摘要
当允许任意全球高斯操作和一般高斯测量值时，我们确定了从某种类别的多模高斯状态及其混合物区分和比较量子状态的最佳方法。我们考虑所谓的常数 - $ \ hat {p} $流离失所的状态，其中包括沿公共轴任意移位的多模相干状态的混合物。我们首先表明，没有比单独应用于每个模式的简单同源测量和结果对结果进行经典的后处理，没有任何全局或局部高斯转换或广义高斯测量值可以带来更好的歧视方法。该结果应用于二元状态比较问题。我们表明，在每种模式下单独执行的同源测量是二进制状态比较的最佳高斯测量。我们进一步比较了使用光子检测的非高斯策略的最佳高斯策略的最佳高斯策略的性能。
We determine the optimal method of discriminating and comparing quantum states from a certain class of multimode Gaussian states and their mixtures when arbitrary global Gaussian operations and general Gaussian measurements are allowed. We consider the so-called constant-$\hat{p}$ displaced states which include mixtures of multimode coherent states arbitrarily displaced along a common axis. We first show that no global or local Gaussian transformations or generalized Gaussian measurements can lead to a better discrimination method than simple homodyne measurements applied to each mode separately and classical postprocessing of the results. This result is applied to binary state comparison problems. We show that homodyne measurements, separately performed on each mode, are the best Gaussian measurement for binary state comparison. We further compare the performance of the optimal Gaussian strategy for binary coherent states comparison with these of non-Gaussian strategies using photon detections.
