Continuous wave lasing between Landau levels in graphene

TL;DR

This paper predicts and designs a continuous wave THz laser using Landau level transitions in graphene under a magnetic field, highlighting its feasibility and potential scalability to other Dirac materials.

Contribution

It introduces a novel scheme for THz lasing in graphene based on Landau level transitions with continuous wave operation under optical pumping.

Findings

Feasibility of continuous wave THz lasing in graphene.

Design principles for the Landau level laser.

Potential scalability to other Dirac materials.

Abstract

We predict the general feasibility and demonstrate the specific design of the THz laser operating between Landau levels in graphene placed on a polar substrate in a magnetic field of order 1 T. Steady state operation under a continuous wave optical pumping is possible due to an interplay between Auger and surface-phonon mediated relaxation of carriers. The scheme is scalable to other materials with massless Dirac fermions, for example surface states in 3D topological insulators such as Bi$_2$Se$_3$ or Bi$_2$Te$_3$.