Visualizing Landau levels of Dirac electrons in a one dimensional potential

TL;DR

This study uses scanning tunneling spectroscopy to investigate how a one-dimensional periodic potential affects Landau levels of Dirac electrons, revealing potential landscape effects on electronic states.

Contribution

It demonstrates how Landau level energies reflect potential variations and uncovers the spatial extent of wavefunctions in Dirac materials with engineered potentials.

Findings

Lower index Landau levels trace potential variations

Higher index levels appear homogeneous

Landau level stripes act as traps for chiral modes

Abstract

Using scanning tunneling spectroscopy we have measured the response of Dirac electrons in a magnetic field to the presence of a well-defined smoothly varying 1D periodic potential. We find that the lower index Landau level energies reliably trace the potential variations, while the higher index levels appear surprisingly homogeneous. Modeling the effects of the periodic potential on the Landau level spectra, we show that the Landau level behavior encodes information on the spatial extent of the wavefunctions. The lower index maps reveal Landau level stripes, which would act as traps for chiral one-dimensional modes. Our findings have important implications for transport and magneto-resistance measurements in Dirac materials with engineered potential landscapes.