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arXiv · 2007.09329

Modeling lasers and saturable absorbers via multilevel atomic media in the Meep FDTD software: Theory and implementation

Alexander Cerjan·Ardavan Oskooi·Song-Liang Chua·Steven G. Johnson
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Abstract

This technical note describes the physical model, numerical implementation, and validation of multilevel atomic media for lasers and saturable absorbers in Meep: a free/open-source finite-difference time-domain (FDTD) software package for electromagnetics simulation. Simulating multilevel media in the time domain involves coupling rate equations for the populations of electronic energy levels with Maxwell's equations via a generalization of the Maxwell--Bloch equations. We describe the underlying equations and their implementation using a second-order discretization scheme, and also demonstrate their equivalence to a quantum density-matrix model. The Meep implementation is validated using a separate FDTD density-matrix model as well as a frequency-domain solver based on steady-state ab-initio laser theory (SALT).

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Alexander Cerjan, Ardavan Oskooi, Song-Liang Chua, Steven G. Johnson. 2020-07-18. Modeling lasers and saturable absorbers via multilevel atomic media in the Meep FDTD software: Theory and implementation. https://arxiv.org/abs/2007.09329

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