Local Density of States and Interface Effects in Semimetallic ErAs Nanoparticles Embedded in GaAs

TL;DR

This study investigates the atomic and electronic structures of ErAs nanoparticles in GaAs, revealing their semimetallic nature and interface effects that prevent band gap opening, challenging previous quantum confinement models.

Contribution

It provides direct experimental evidence of the semimetallic LDOS in ErAs nanoparticles and links interface atomic structure to electronic properties, offering new insights into nanoparticle behavior.

Findings

ErAs nanoparticles remain semimetallic despite quantum confinement predictions

Interface atomic structure influences electronic states preventing band gap formation

Local density of states shows a finite minimum at the Fermi level

Abstract

The atomic and electronic structures of ErAs nanoparticles embedded within a GaAs matrix are examined via cross-sectional scanning tunneling microscopy and spectroscopy (XSTM/XSTS). The local density of states (LDOS) exhibits a finite minimum at the Fermi level demonstrating that the nanoparticles remain semimetallic despite the predictions of previous models of quantum confinement in ErAs. We also use XSTS to measure changes in the LDOS across the ErAs/GaAs interface and propose that the interface atomic structure results in electronic states that prevent the opening of a band gap.