Spectral hole burning and gain saturation in short-cavity semiconductor lasers

Abstract

A coupled set of equations for carrier distributions and stimulated emission in a semiconductor laser is presented, based on a nonequilibrium Green s-function formulation. Carrier momentum-dependent dephasing caused by carrier-carrier scattering and frequency-dependent optical gain are shown to govern the interplay between carrier relaxation and stimulated recombination. Ignoring the interband Coulomb interaction, the coupled system of equations for the carrier distribution functions and the optical gain is solved self-consistently for a single-mode short-cavity semiconductor laser under steady-state operation conditions. Numerical results show spectral and kinetic hole burning as well as nonlinear gain saturation.PACS number(s): 42.55.Px, 42.65. -k

Semiclassical theory for a nonequilibrium steady state in microcavity semiconductor lasers

“…The small increase of the carrier distribution at the highmomentum is due to the stimulated absorbtion of photons. The similar results are also found in [9]. …”

“…Terms ∝ κ, γ and 1/T are introduced phenomenologically to include the loss and pump of lasers. In the past, the relaxation rate 1/T was calculated microscopically within a Born approximation and a dynamical random-phase approximation [12,9], where the carrier distribution and the kinetic hole are shown to be related to the rate. The self-consistent determination of the rate will be important to discuss the shape of kinetic hole quantitatively, however the detailed analysis is out of scope of the qualitative discussions here.…”

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Principles and Methods of Quantum Information Technologies

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Generation of Terahertz radiation with two color semiconductor lasers

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