Virtual Scanning Tunneling Microscopy: A Local Spectroscopic Probe of 2D Electron Systems

TL;DR

This paper introduces a new local spectroscopic technique using a charged tip to probe 2D electron systems with high spatial resolution and minimal disturbance, enabling detailed study of electron phases in semiconductor heterostructures.

Contribution

It proposes and tests a novel tunneling-based probe method for local spectroscopy of 2DES, offering high spatial resolution and minimal perturbation.

Findings

Predicted high spatial resolution and spectroscopic capability.

Demonstrated minimal influence on the subject 2DES.

Validated the concept with large-area tunneling measurements.

Abstract

We propose a novel probe technique capable of performing local low-temperature spectroscopy on a 2D electron system (2DES) in a semiconductor heterostructure. Motivated by predicted spatially-structured electron phases, the probe uses a charged metal tip to induce electrons to tunnel locally, directly below the tip, from a "probe" 2DES to a "subject" 2DES of interest. We test this concept with large-area (non-scanning) tunneling measurements, and predict a high spatial resolution and spectroscopic capability, with minimal influence on the physics in the subject 2DES.