Electrically tunable inverse spin Hall effect in SrIrO3/Pb(Mg1/3Nb2/3)0.7 Ti0.3O3 heterostructures through interface strain coupling

Abstract

Oxide spin detector materials are highly desired for emergent all-oxide spintronics. In this work, Permalloy/SrIrO₃/Pb(Mg_1/3Nb_2/3)_0.7 Ti_0.3O₃ (Py/SIO/PMNPT) heterostructures were prepared by pulsed laser deposition of SIO thin films epitaxially on (001)-oriented single crystalline PMNPT substrates, followed by sputter deposition of Py films upon SIO through a shadow mask. The paramagnetic SIO layer, with a large spin–orbit coupling, serves as a detector to check the spin current pumped from the adjacent ferromagnetic Py layer through the inverse spin Hall effect (ISHE). It is observed that the spin pumping amplitude can be reversibly tuned by about 50% through applying a 10 kV/cm electric field on the piezoelectric PMNPT substrate. The ISHE voltage shows a butterfly hysteresis resembling the strain-field curve of PMNPT, indicating the relevance of strain coupling at the SIO/PMNPT interface. In situ x-ray diffraction reveals that both in-plane and out-of-plane lattice parameters of SIO vary with the field applied on PMNPT. These results highlight that SIO is a promising candidate material for spin detection, and the efficiency of spin to charge conversion in SIO can be tuned electrically in SIO/PMNPT heterostructures.