Enhanced electron correlations in FeSb$_2$

TL;DR

FeSb$_2$ is a narrow gap semiconductor exhibiting strong electron correlations affecting various physical properties, with recent studies highlighting its potential as a model system for many-body effects in $d$-electron materials.

Contribution

This paper reviews experimental evidence of correlation effects in FeSb$_2$ and discusses the impact of Te doping on its electronic properties.

Findings

Strong electron correlations influence transport and magnetic properties.

Te doping induces a metallic state with large quasiparticle mass.

Correlation effects are crucial for understanding FeSb$_2$'s physical behavior.

Abstract

FeSb$_2$ has been recently identified as a new model system for studying many-body renormalizations in a $d$-electron based narrow gap semiconducting system, strongly resembling FeSi. The electron-electron correlations in FeSb$_2$ manifest themselves in a wide variety of physical properties including electrical and thermal transport, optical conductivity, magnetic susceptibility, specific heat and so on. We review some of the properties that form a set of experimental evidences revealing the crucial role of correlation effects in FeSb$_2$. The metallic state derived from slight Te doping in FeSb$_2$, which has large quasiparticle mass, will also be introduced.