论文标题
用于估计量子渔民信息的变分量子算法
Variational Quantum Algorithm for Estimating the Quantum Fisher Information
论文作者
论文摘要
量子Fisher信息（QFI）量化了从量子状态估算参数的最终精度，并且可以被视为量子系统作为量子传感器的可靠性度量。但是，对混合状态的QFI的估计通常是计算要求的任务。在这项工作中，我们提出了一种称为变异量子Fisher信息估计（VQFIE）的变异量子算法，以解决此任务。通过估算QFI上的下限和上限，基于限制忠诚度，VQFIE输出了实际QFI所处的范围。然后，该结果可用于变化制备最大化QFI的状态，以应用量子传感。与以前的方法相反，VQFIE不需要了解传感器动力学的明确形式。我们为磁力测定设置模拟算法，并随着状态纯度的增加而演示我们边界的拧紧。在此示例中，我们将界限与文学界限进行比较，并表明我们的界限更加紧密。
The Quantum Fisher information (QFI) quantifies the ultimate precision of estimating a parameter from a quantum state, and can be regarded as a reliability measure of a quantum system as a quantum sensor. However, estimation of the QFI for a mixed state is in general a computationally demanding task. In this work we present a variational quantum algorithm called Variational Quantum Fisher Information Estimation (VQFIE) to address this task. By estimating lower and upper bounds on the QFI, based on bounding the fidelity, VQFIE outputs a range in which the actual QFI lies. This result can then be used to variationally prepare the state that maximizes the QFI, for the application of quantum sensing. In contrast to previous approaches, VQFIE does not require knowledge of the explicit form of the sensor dynamics. We simulate the algorithm for a magnetometry setup and demonstrate the tightening of our bounds as the state purity increases. For this example, we compare our bounds to literature bounds and show that our bounds are tighter.
