论文标题
量子Fisher信息的广义量度
Generalized Measure of Quantum Fisher Information
论文作者
论文摘要
在这项工作中，我们介绍了量子渔民信息（QFI）的下限，该信息可在近期量子设备上有效地计算。这种界限本身引起了人们的关注，因为我们表明它满足了QFI度量的规范标准。具体而言，它本质上是对亚伸展状态的QFI度量，因此从这个意义上讲，它概括了标准QFI。我们的界限采用了应用于截断状态的广义保真度，该保真度是通过$ m $最大的特征值及其相应的探针量子状态$ρ_θ$的相应特征向量构建的。为了关注精确状态的统一家族，我们分析了我们提出的下限的性质，并证明了其有效估计QFI的实用性。
In this work, we present a lower bound on the quantum Fisher information (QFI) which is efficiently computable on near-term quantum devices. This bound itself is of interest, as we show that it satisfies the canonical criteria of a QFI measure. Specifically, it is essentially a QFI measure for subnormalized states, and hence it generalizes the standard QFI in this sense. Our bound employs the generalized fidelity applied to a truncated state, which is constructed via the $m$ largest eigenvalues and their corresponding eigenvectors of the probe quantum state $ρ_θ$. Focusing on unitary families of exact states, we analyze the properties of our proposed lower bound, and demonstrate its utility for efficiently estimating the QFI.
