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arXiv · 2308.16715

Carrier diffusion in semiconductor nanoscale resonators

Marco Saldutti·Yi Yu·George Kountouris·Philip Trøst Kristensen·Jesper Mørk
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Abstract

It is shown that semiconductor nanoscale resonators with extreme dielectric confinement accelerate the diffusion of electron-hole pairs excited by nonlinear absorption. These novel cavity designs may lead to optical switches with superior modulation speeds compared to conventional geometries. The response function of the effective carrier density is computed by an efficient eigenmode expansion technique. A few eigenmodes of the diffusion equation conveniently capture the long-timescale carrier decay rate, which is advantageous compared to time-domain simulations. Notably, the eigenmode approach elucidates the contribution to carrier diffusion of the in-plane and out-of-plane cavity geometry, which may guide future designs.

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Marco Saldutti, Yi Yu, George Kountouris, Philip Trøst Kristensen, Jesper Mørk. 2023-08-31. Carrier diffusion in semiconductor nanoscale resonators. https://arxiv.org/abs/2308.16715

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