Theoretical and experimental analysis of rare earth whispering gallery mode laser relative intensity noise

TL;DR

This paper investigates the relative intensity noise of a solid state whispering-gallery-mode laser through theoretical modeling and experimental validation, revealing harmonic structures and providing insights into laser noise characteristics.

Contribution

It introduces a rate equation model with Langevin forces and nonlinear coupling to accurately reproduce RIN spectra and extract physical parameters.

Findings

Harmonics of spiking frequency observed in RIN spectrum

Model successfully fits experimental data

Provides physical insights into laser noise mechanisms

Abstract

The relative intensity noise (RIN) of a solid state whispering-gallery-mode class-B laser is studied both theoretically and experimentally under different pumping regimes. In particular, we show that harmonics of the spiking frequency are observed in the RIN spectrum. A rate equation model including Langevin forces and the nonlinear coupling between inverted ion and photon number fluctuations has been developed to reproduce the experimental results and to extract relevant physical parameters from the fitting of the RIN spectrum.