Anomalous Spin and Orbital Hall Phenomena in Antiferromagnetic Systems

TL;DR

This paper reports the discovery of strong anomalous spin and orbital Hall effects in antiferromagnetic materials, achieved through orbital pumping experiments, revealing new mechanisms for spin-orbitronics applications.

Contribution

It introduces the concept of an orbital Hall angle as a tensor, expanding understanding of spin-orbital current conversion in antiferromagnetic systems.

Findings

Sevenfold increase in anomalous inverse orbital Hall effect signals

Observation of strong out-of-plane spin and orbital signals in AF heterostructures

Proposal of a rank 3 tensor for orbital Hall angle to explain effects

Abstract

We investigate anomalous spin and orbital Hall phenomena in antiferromagnetic (AF) materials via orbital pumping experiments. Conducting spin and orbital pumping experiments on YIG/Pt/Ir20Mn80 heterostructures, we unexpectedly observe strong spin and orbital anomalous signals in an out-of-plane configuration. We report a sevenfold increase in the signal of the anomalous inverse orbital Hall effect (AIOHE) compared to conventional effects. Our study suggests expanding the Orbital Hall angle ({\theta}_OH) to a rank 3 tensor, akin to the Spin Hall angle ({\theta}_SH), to explain AIOHE. This work pioneers converting spin-orbital currents into charge current, advancing the spin-orbitronics domain in AF materials.