Quasiparticle interference and quantum confinement in a correlated Rashba spin-split 2D electron liquid

TL;DR

This paper investigates a correlated Rashba spin-split 2D electron liquid, revealing how spin-orbital interactions influence quasiparticle scattering and coherence, with implications for spintronic device miniaturization.

Contribution

It demonstrates that spin-orbital selection rules govern quasiparticle scattering in a correlated Rashba system, affecting spin coherence length and offering insights for spintronic applications.

Findings

Spin-orbital selection rules are obeyed as true spin selection rules.

Quasiparticle interference imaging determines spin coherence length.

Large Rashba spin splitting observed in transition metal oxide terminations.

Abstract

Exploiting inversion symmetry breaking (ISB) in systems with strong spin-orbit coupling promises control of spin through electric fields - crucial to achieve miniaturization in spintronic devices. Delivering on this promise requires a two-dimensional electron gas with a spin precession length shorter than the spin coherence length and a large spin splitting so that spin manipulation can be achieved over length scales of nanometers. Recently, the transition metal oxide terminations of delafossite oxides were found to exhibit a large Rashba spin splitting dominated by ISB. In this limit, the Fermi surface exhibits the same spin texture as for weak ISB, but the orbital texture is completely different, raising questions about the effect on quasiparticle scattering. We demonstrate that the spin-orbital selection rules relevant for conventional Rashba system are obeyed as true spin selection rules in this correlated electron liquid and determine its spin coherence length from quasiparticle interference imaging.