All-electrical detection of the spin-charge conversion in nanodevices based on SrTiO3 two-dimensional electron gases

TL;DR

This paper demonstrates all-electrical spin-injection and spin-charge conversion in nanoscale SrTiO3 2DEG devices, highlighting their potential for energy-efficient, non-volatile logic applications beyond traditional CMOS technology.

Contribution

It reports the first all-electrical spin-injection and spin-charge conversion experiments in SrTiO3 2DEG nanodevices, optimizing signals and analyzing temperature effects.

Findings

Successful electrical spin injection and charge conversion in SrTiO3 2DEG devices

Enhanced spin-charge conversion signal via back-gate voltage tuning

Disentanglement of inverse Edelstein effect from spurious effects

Abstract

The Magnetoelectric Spin-Orbit (MESO) technology aims to bring logic into memory by combining a ferromagnet with a magnetoelectric (ME) element for information writing, and a spin-orbit (SO) element for information read-out through spin-charge conversion. Among candidate SO materials to achieve a large MESO output signal, oxide Rashba two-dimensional electron gases (2DEGs) have shown very large spin-charge conversion efficiencies, albeit mostly in spin-pumping experiments. Here, we report all-electrical spin-injection and spin-charge conversion experiments in nanoscale devices harnessing the inverse Edelstein effect of SrTiO3 2DEGs. We have designed, patterned and fabricated nanodevices in which a spin current injected from a cobalt layer into the 2DEG is converted into a charge current. We optimized the spin-charge conversion signal by applying back-gate voltages, and studied its temperature evolution. We further disentangled the inverse Edelstein contribution from spurious effects such as the planar Hall effect, the anomalous Hall effect or the anisotropic magnetoresistance. The combination of non-volatility and high energy efficiency of these devices could potentially lead to new technology paradigms for beyond-CMOS computing architectures.