Spin and charge interconversion in Dirac semimetal thin films

TL;DR

This study demonstrates room-temperature spin-charge interconversion in Dirac semimetal thin films interfaced with ferromagnets, showing potential for spintronic applications with efficiencies comparable to heavy metals.

Contribution

First experimental observation of spin-charge interconversion in Dirac semimetal Cd3As2 at room temperature with detailed analysis and comparison to theoretical models.

Findings

Spin-charge conversion efficiency comparable to heavy metals.

Consistent behavior with known spin-charge mechanisms.

Effective at room temperature in heterostructures.

Abstract

We report spin-to-charge and charge-to-spin conversion at room temperature in heterostructure devices that interface an archetypal Dirac semimetal, Cd3As2, with a metallic ferromagnet, Ni0.80Fe0.20 (permalloy). The spin-charge interconversion is detected by both spin torque ferromagnetic resonance and ferromagnetic resonance driven spin pumping. Analysis of the symmetric and anti-symmetric components of the mixing voltage in spin torque ferromagnetic resonance and the frequency and power dependence of the spin pumping signal show that the behavior of these processes is consistent with previously reported spin-charge interconversion mechanisms in heavy metals, topological insulators, and Weyl semimetals. We find that the efficiency of spin-charge interconversion in Cd3As2/permalloy bilayers can be comparable to that in heavy metals. We discuss the underlying mechanisms by comparing our results with first principles calculations.