Engineering artificial graphene in a two-dimensional electron gas

TL;DR

This paper proposes creating artificial graphene in a two-dimensional electron gas by applying a honeycomb periodic potential, enabling the study of Dirac fermion physics in semiconductor systems.

Contribution

It introduces a method to engineer Dirac points in a 2D electron gas using a honeycomb potential, with detailed theoretical estimates and potential experimental realization.

Findings

Artificial graphene-like Dirac points can be created in 2D electron gases.

Fermi velocity of Dirac points is tunable via potential modulation.

Potential for studying Dirac physics in high-mobility semiconductor systems.

Abstract

At low energy, electrons in doped graphene sheets behave like massless Dirac fermions with a Fermi velocity which does not depend on carrier density. Here we show that modulating a two-dimensional electron gas with a long-wavelength periodic potential with honeycomb symmetry can lead to the creation of isolated massless Dirac points with tunable Fermi velocity. We provide detailed theoretical estimates to realize such artificial graphene-like system and discuss an experimental realization in a modulation-doped GaAs quantum well. Ultra high-mobility electrons with linearly-dispersing bands might open new venues for the studies of Dirac-fermion physics in semiconductors.