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arXiv · 1908.03496

Fundamental limits to far-infrared lasing in Auger-suppressed HgCdTe quantum wells

Georgy Alymov·Vladimir Rumyantsev·Sergey Morozov·Vladimir Gavrilenko·Vladimir Aleshkin·Dmitry Svintsov
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Abstract

A challenge of bridging the terahertz gap with semiconductor lasers faces an inevitable problem of enhanced non-radiative Auger recombination with reduction of photon energy. We show that this problem can be mitigated in mercury-cadmium-telluride quantum wells (HgCdTe QWs) wherein the Auger process is suppressed due to formation of quasi-relativistic electron-hole dispersion imposing strong energy-momentum restrictions on recombining carriers. Such dispersion is formed upon interaction of topological states at the two QW interfaces. We characterize the lasing properties of HgCdTe QWs quantitatively by constructing a microscopic theory for recombination, absorption, and gain, and show the feasibility of lasing down to ~ 50 $μ$m at liquid nitrogen temperature with threshold currents two orders of magnitude lower than in existing lasers. Our findings comply with recent experimental data on stimulated far-infrared emission from HgCdTe QWs and show the directions toward achievement of maximum possible lasing wavelength.

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Georgy Alymov, Vladimir Rumyantsev, Sergey Morozov, Vladimir Gavrilenko, Vladimir Aleshkin, Dmitry Svintsov. 2019-08-09. Fundamental limits to far-infrared lasing in Auger-suppressed HgCdTe quantum wells. https://arxiv.org/abs/1908.03496

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