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arXiv · 1307.3792

Transient stimulated emission from multi-split-gated graphene structure

A. Satou·F. T. Vasko·T. Otsuji·V. V. Mitin
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Abstract

Mechanism of transient population inversion in graphene with multi-splitted (interdigitated) top-gate and grounded back gate is suggested and examined for the mid-infrared (mid-IR) spectral region. Efficient stimulated emission after fast lateral spreading of carriers due to drift-diffusion processes is found for the case of a slow electron-hole recombination in the passive region. We show that with the large gate-to-graphene distance the drift process always precedes the diffusion process, due to the ineffective screening of the inplane electric field by the gates. Conditions for lasing with a gain above 100 cm$^{-1}$ are found for cases of single- and multi-layer graphene placed in the waveguide formed by the top and back gates. Both the waveguide losses and temperature effects are analyzed.

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A. Satou, F. T. Vasko, T. Otsuji, V. V. Mitin. 2013-07-14. Transient stimulated emission from multi-split-gated graphene structure. https://doi.org/10.1088/0022-3727/47/5/055103

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