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arXiv · 1309.2724

Injection terahertz laser using the resonant inter-layer radiative transitions in double-graphene-layer structure

V. Ryzhii·A. A. Dubinov·V. Ya. Aleshkin·M. Ryzhii·T. Otsuji
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Abstract

We propose and substantiate the concept of terahertz (THz) laser enabled by the resonant electron radiative transitions between graphene layers (GLs) in double-GL structures. We estimate the THz gain for TM-mode exhibiting very low Drude absorption in GLs and show that the gain can exceed the losses in metal-metal waveguides at the low end of the THz range. The spectrum of the emitted photons can be tuned by the applied voltage. A weak temperature dependence of the THz gain promotes an effective operation at room temperature.

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V. Ryzhii, A. A. Dubinov, V. Ya. Aleshkin, M. Ryzhii, T. Otsuji. 2013-09-11. Injection terahertz laser using the resonant inter-layer radiative transitions in double-graphene-layer structure. https://doi.org/10.1063/1.4826113

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