Probing the nodal structure of Landau level wave functions in real space

TL;DR

This study uses scanning tunnelling spectroscopy to visualize the nodal structure of Landau level wave functions in real space within a smooth potential landscape, revealing distinct nodal patterns for different Landau levels.

Contribution

It provides the first real-space visualization of Landau level wave functions' nodal structures and validates the findings with both experimental data and theoretical models.

Findings

Zeroth Landau level shows single peak and ring structure.

First Landau level exhibits double peaks and double rings.

Results are consistent across experimental data and theoretical models.

Abstract

The inversion layer of p-InSb(110) obtained by Cs adsorption of 1.8 % of a monolayer is used to probe the Landau level wave functions within smooth potential valleys by scanning tunnelling spectroscopy at 14 T. The nodal structure becomes apparent as a double peak structure of each spin polarized first Landau level, while the zeroth Landau level exhibits a single peak per spin level only. The real space data show single rings of the valley-confined drift states for the zeroth Landau level and double rings for the first Landau level. The result is reproduced by a recursive Green's function algorithm using the potential landscape obtained experimentally. We show that the result is generic by comparing the local density of states from the Green's function algorithm with results from a well controlled analytic model based on the guiding center approach.