Fe/GeTe(111) heterostructures as an avenue towards 'ferroelectric Rashba semiconductors'-based spintronics

TL;DR

This study investigates Fe/GeTe(111) heterostructures using DFT, spectroscopy, and Green's functions, revealing their potential for spintronics due to unique interplay of magnetic, electric, and spin-orbit effects.

Contribution

It demonstrates how Fe/GeTe(111) interfaces maintain bulk Rashba bands despite strong hybridization, highlighting their suitability for spintronic applications.

Findings

Bulk Rashba bands are preserved despite hybridization.

Surface states are suppressed by the Fe overlayer.

Interplay of exchange, polarization, and spin-orbit coupling is significant.

Abstract

By performing density functional theory (DFT) and Green's functions calculations, complemented by X-ray Photoemission Spectroscopy, we investigate the electronic structure of Fe/GeTe(111), a prototypical ferromagnetic/Rashba-ferroelectric interface. We reveal that such system exhibits several intriguing properties resulting from the complex interplay of exchange interaction, electric polarization and spin-orbit coupling. Despite a rather strong interfacial hybridization between Fe and GeTe bands, resulting in a complete suppression of the surface states of the latter, the bulk Rashba bands are hardly altered by the ferromagnetic overlayer. This could have a deep impact on spin dependent phenomena observed at this interface, such as spin-to-charge interconversion, which are likely to involve bulk rather than surface Rashba states.