Quantum Noise of Free-Carrier Dispersion in Semiconductor Optical Cavities

TL;DR

This paper models quantum noise in semiconductor optical cavities with free-carrier dispersion, deriving stochastic equations to simulate their behavior and compare with Kerr models, revealing additional noise effects.

Contribution

It introduces a generalized Wigner function and stochastic differential equations for free-carrier nonlinearities, extending quantum noise analysis beyond Kerr models.

Findings

Additional noise terms due to incoherent carrier processes

Simulation results show differences from Kerr cavity models

Framework enables quantum noise analysis in semiconductor cavities

Abstract

This paper derives Langevin equations for an optical cavity where the dominant nonlinearity arises from free-carrier dispersion. We define a generalized Wigner function, compute a Fokker-Planck equation that approximates the master equation, and convert this to a system of stochastic differential equations. These equations are similar to the Wigner equations for an optical Kerr cavity, but have additional noise terms due to the incoherent carrier excitation and decay processes. We use these equations to simulate a phase-sensitive amplifier and latch and compare the results to a Kerr model.