Photoemission spectra of massless Dirac fermions on the verge of exciton condensation

TL;DR

This paper proposes using ARPES to detect the onset of exciton condensation in two-dimensional electron-hole systems, such as double-layer graphene and topological insulators, providing a new experimental approach.

Contribution

It introduces a novel application of ARPES to identify exciton condensation in spatially-separated electron-hole systems.

Findings

ARPES can detect signatures of exciton condensation.

The method applies to double-layer graphene and topological insulators.

Provides a new experimental tool for studying electron-hole interactions.

Abstract

Angle-resolved photoemission spectroscopy (ARPES) is a powerful probe of electron correlations in two-dimensional layered materials. In this Letter we demonstrate that ARPES can be used to probe the onset of exciton condensation in spatially-separated systems of electrons and holes created by gating techniques in either double-layer graphene or topological-insulator thin films.