Noise spectroscopy of the optical microcavity: nonlinear amplification of the spin noise signal and giant noise

TL;DR

This paper investigates the Kerr rotation noise in an optical microcavity with a quantum well, revealing giant noise amplification due to nonlinear instability, especially near polariton anti-crossing, and models this built-in amplification effect.

Contribution

It introduces a model explaining the nonlinear amplification of spin noise in microcavities, highlighting the giant noise phenomenon near polariton anti-crossing.

Findings

Giant noise amplification observed near polariton anti-crossing

Nonlinear instability causes significant noise enhancement

Model describes noise behavior at negative detuning

Abstract

The spin-fluctuations-related Kerr rotation noise of the optical beam reflected from a microcavity with a quantum well in the intermirror gap is studied. In the regime of anti-crossing of the cavity polariton branches, the several hundred times enhancement of the noise signal, or giant noise, is observed. The effect of the amplification of the noise signal is explained by the nonlinear instability of the microcavity. In the frame of the developed model of built-in amplifier, the non-trivial properties of the noise signal in the regime of the negative detuning of microcavity are described.