Magnetic-field-dependent zero-bias diffusive anomaly in Pb oxide-n-InAs structures: Coexistence of two- and three-dimensional states

TL;DR

This study investigates the zero-bias anomaly in Pb-oxide-n-InAs tunnel structures under magnetic fields, revealing the coexistence of 2D and 3D electronic states and their influence on tunneling behavior.

Contribution

It provides a combined experimental and theoretical analysis of ZBA in structures with coexisting 2D and 3D states, highlighting the magnetic field effects.

Findings

ZBA amplitude depends on magnetic field strength and orientation

Electrons tunnel into 2D states and move diffusively within them

Screening is primarily contributed by 3D electrons

Abstract

The results of experimental and theoretical studies of zero-bias anomaly (ZBA) in the Pb-oxide-n-InAs tunnel structures in magnetic field up to 6T are presented. A specific feature of the structures is a coexistence of the 2D and 3D states at the Fermi energy near the semiconductor surface. The dependence of the measured ZBA amplitude on the strength and orientation of the applied magnetic field is in agreement with the proposed theoretical model. According to this model, electrons tunnel into 2D states, and move diffusively in the 2D layer, whereas the main contribution to the screening comes from 3D electrons.