Nanometer scale electronic reconstruction at the interface between LaVO3 and LaVO4

TL;DR

This study reveals a nanometer-scale electronic reconstruction at the LaVO3/LaVO4 interface, where a unique V 3d1 electron configuration forms despite no bulk phase existing with this state, highlighting complex interfacial electron behavior.

Contribution

The paper demonstrates the presence of a nanometer-wide V 3d1 region at the LaVO3/LaVO4 interface, a novel electronic reconstruction not observed in bulk phases.

Findings

Identification of a V 3d1 region at the interface

Absence of bulk LaVOx with V 3d1 configuration

Electronic reconstruction at heterovalent interface

Abstract

Electrons at interfaces, driven to minimize their free energy, are distributed differently than in bulk. This can be dramatic at interfaces involving heterovalent compounds. Here we profile an abrupt interface between V 3d2 LaVO3 and V 3d0 LaVO4 using electron energy loss spectroscopy. Although no bulk phase of LaVOx with a V 3d1 configuration exists, we find a nanometer-wide region of V 3d1 at the LaVO3/LaVO4 interface, rather than a mixture of V 3d0 and V 3d2. The two-dimensional sheet of 3d1 electrons is a prototypical electronic reconstruction at an interface between competing ground states.