Optimal Measurement on Noisy Quantum Systems

TL;DR

This paper determines the best measurement strategies for extracting information from noisy quantum systems, quantifies their effectiveness, and applies these findings to a quantum control scenario involving a spin-boson model.

Contribution

It introduces a method to identify optimal measurements for noisy quantum states and quantifies the information gain, advancing quantum measurement theory.

Findings

Optimal measurement maximizes Fisher information in noisy conditions

Quantitative analysis of information loss due to decoherence

Application to quantum control in spin-boson systems

Abstract

We identify the optimal measurement for obtaining information about the original quantum state after the state to be measured has undergone partial decoherence due to noise. We quantify the information that can be obtained by the measurement in terms of the Fisher information and find its value for the optimal measurement. We apply our results to a quantum control scheme based on a spin-boson model.