Coherent-feedback quantum control with a dynamic compensator

TL;DR

This paper demonstrates an experimental coherent-feedback control system using an optical ring-resonator, achieving significant broadband disturbance rejection through all-optical feedback with a dynamic compensator, validating theoretical principles of quantum control.

Contribution

It provides the first experimental realization of a coherent-feedback quantum control system with a dynamic compensator, confirming theoretical predictions and identifying key performance parameters.

Findings

Achieved ~7 dB broadband disturbance rejection.

Validated transfer function model predictions.

Demonstrated all-optical feedback control in a quantum system.

Abstract

I present an experimental realization of a coherent-feedback control system that was recently proposed for testing basic principles of linear quantum stochastic control theory [M. R. James, H. I. Nurdin and I. R. Petersen, to appear in IEEE Transactions on Automatic Control (2008), arXiv:quant-ph/0703150v2]. For a dynamical plant consisting of an optical ring-resonator, I demonstrate ~ 7 dB broadband disturbance rejection of injected laser signals via all-optical feedback with a tailored dynamic compensator. Comparison of the results with a transfer function model pinpoints critical parameters that determine the coherent-feedback control system's performance.