Effects of time delay in feedback control of linear quantum systems

TL;DR

This paper analyzes how time delays in feedback loops affect the control performance of linear quantum systems, providing theoretical insights and guidelines for experimental setups.

Contribution

It offers a theoretical framework linking feedback delay to control performance in linear quantum systems, based on classical control theory.

Findings

Control performance decreases with increasing feedback delay

Provides guidelines for experimental design in quantum control systems

Connects classical delay system theory to quantum feedback control

Abstract

We investigate feedback control of linear quantum systems subject to feedback-loop time delays. In particular, we examine the relation between the potentially achievable control performance and the time delays, and provide theoretical guidelines for the future experimental setup in two physical systems, which are typical in this research field. The evaluation criterion for the analysis is given by the optimal control performance formula, the derivation of which is from the classical control theoretic results about the input-output delay systems.