Spin and Charge Interconversion in Dirac-Semimetal Thin Films
Wilson Yanez, Yongxi Ou, Run Xiao, Jahyun Koo, Jacob T. Held, Supriya Ghosh, Jeffrey Rable, Timothy Pillsbury, Enrique González Delgado, Kezhou Yang, Juan Chamorro, Alexander J. Grutter, Patrick Quarterman, Anthony Richardella, Abhronil Sengupta, Tyrel McQueen, Julie A. Borchers, K. Andre Mkhoyan, Binghai Yan, Nitin Samarth
Abstract
Understanding spin-charge interconversion (SCI) in topological quantum materials, such as Dirac semimetals, is important for developing energy-efficient spintronic memory. This article reports room-temperature measurements of SCI at the interface between an archetypal Dirac semimetal (Cd${}_{3}$As${}_{2}$) and a metallic ferromagnet (Ni${}_{0.8}$Fe${}_{0.2}$). Analysis shows that a Dirac semimetal can have a SCI efficiency similar to that of heavy metals and topological insulators. Surprisingly, the highest efficiency is associated with extrinsic effects due to imperfect (oxidized) interfaces. These results suggest caution in attributing spin transport solely to the topological states of Cd${}_{3}$As${}_{2}$.