Ferroelectricity and Rashba effect in GeTe

TL;DR

This paper demonstrates that GeTe exhibits both ferroelectricity and Rashba effects, with surface and bulk Rashba bands influenced by its ferroelectric polarization, enabling potential control of spin properties.

Contribution

It provides experimental evidence linking ferroelectricity and Rashba effects in GeTe, highlighting its potential as a ferroelectric Rashba semiconductor.

Findings

GeTe shows surface and bulk Rashba bands due to ferroelectric polarization.

The Rashba effect in GeTe can be controlled via its ferroelectric polarization.

Experimental results agree with first-principles calculations.

Abstract

GeTe has been proposed as the father compound of a new class of functional materials displaying bulk Rashba effects coupled to ferroelectricity: ferroelectric Rashba semiconductors. In nice agreement with first principle calculations, we show by angular resolved photoemission and piezo-force microscopy that GeTe displays surface and bulk Rashba bands arising from the intrinsic inversion symmetry breaking provided by the remanent ferroelectric polarization. This work points to the possibility to control the spin chirality of bands in GeTe by acting on its ferroelectric polarization.