Feedback control of the fluorescence light squeezing

TL;DR

This paper investigates how Wiseman-Milburn feedback control can enhance the squeezing of fluorescence light emitted by a two-level atom driven by a laser, using quantum trajectory theory to analyze the effects of control parameters.

Contribution

It introduces a feedback mechanism based on homodyne detection to improve light squeezing and atom properties, providing a detailed analysis of control parameter effects.

Findings

Feedback enhances fluorescence light squeezing.

Control parameters significantly influence squeezing properties.

Relations among atom and light squeezing are elucidated.

Abstract

We consider a two-level atom stimulated by a coherent monochromatic laser and we study how to enhance the squeezing of the fluorescence light and of the atom itself in the presence of a Wiseman-Milburn feedback mechanism, based on the homodyne detection of a fraction of the emitted light. Besides analyzing the effect of the control parameters on the squeezing properties of the light and of the atom, we also discuss the relations among these. The problem is tackled inside the framework of quantum trajectory theory.