The origin of electron-hole asymmetry in graphite

TL;DR

This paper investigates the electron-hole asymmetry in graphite using magneto-optical measurements, confirming theoretical predictions and suggesting similar effects in graphene.

Contribution

It provides experimental evidence of electron-hole asymmetry in graphite consistent with the SWM Hamiltonian, highlighting the role of trigonal warping.

Findings

Observed splitting at K and H points in graphite

Consistent with SWM Hamiltonian predictions

Implication for electron-hole asymmetry in graphene

Abstract

The electron hole asymmetry has been measured in natural graphite using magneto-optical absorption measurements. A splitting is observed for the transitions at both the $K$-point and the $H$-point of the Brillouin zone of graphite where the effect of trigonal warping vanishes. This result is fully consistent with the SWM Hamiltonian providing the free electron kinetic energy terms are taken into account. An identical electron-hole asymmetry should be present in graphene.