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

TL;DR

This paper proposes a terahertz laser based on resonant inter-layer transitions in double-graphene-layer structures, demonstrating potential for room-temperature operation with tunable emission and low absorption losses.

Contribution

It introduces a novel THz laser concept utilizing resonant electron transitions in double-graphene layers, with estimated gain surpassing losses at low THz frequencies.

Findings

THz gain can exceed waveguide losses at low frequencies

Emission spectrum is tunable via applied voltage

Operation is effective at room temperature

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.