Piezostrain control of orbital Rashba effect in Py/CuOx/PMN-PT heterostructures

Electric-field modulated magnetic properties have attracted numerous research studies to elucidate the underlying physics and develop practical electronic devices. In this work, it is demonstrated that the orbital Rashba effect can be modulated by the applied electric field, which is reflected by the variation of charge-to-orbital conversion efficiency ξ under different electric fields in Py/CuOx/PMN-PT heterostructures, where ξ displays a butterfly-like behavior with the electric field, which can be attributed to the piezostrain-mediated magnetoelectric coupling, thus realizing the effective modulation of orbital torque related to the orbital Rashba effect. In addition, our first-principles calculations demonstrate that the orbital moment increases upon increasing strain, which stems from the enhanced p–d hybridization of the interfaced O and Cu atoms. Our results provide a method for modulating the orbital Rashba effect and charge-to-orbital conversion, which shows good potential for practical applications.