Quantification of interfacial spin-charge conversion in metal/insulator hybrid structures by generalized boundary conditions

Abstract

We present and verify experimentally a universal theoretical framework for the description of spin-charge interconversion in non-magnetic metal/insulator structures with interfacial spin-orbit coupling (ISOC). Our formulation is based on drift-diffusion equations supplemented with generalized boundary conditions. The latter encode the effects of ISOC and relate the electronic transport in such systems to spin loss and spin-charge interconversion at the interface, which are parameterized, respectively, by $G_{\parallel /\perp }$ and ${\sigma }_{sc/cs}$. We demonstrate that the conversion efficiency depends solely on these interfacial parameters. We apply our formalism to two typical spintronic devices that exploit ISOC: a lateral spin valve and a multilayer Hall bar, for which we calculate the non-local resistance and the spin Hall magnetoresistance, respectively. Finally, we perform measurements on these two devices with a BiO${}_x$/Cu interface and verify that transport properties related to the ISOC are quantified by the same set of interfacial parameters.

References in corpus (10)

• Direct electronic measurement of the spin Hall effect
• Emergent Phenomena Induced by Spin-Orbit Coupling at Surfaces and Interfaces
• Theory of spin Hall magnetoresistance
• Highly efficient and tuneable spin-to-charge conversion through Rashba coupling at oxide interfaces
• Rashba-Edelstein Magnetoresistance in Metallic Heterostructure
• Ballistic spin transport in the presence of interfaces with strong spin-orbit coupling
• Evaluation of bulk-interface contributions to Edelstein magnetoresistance at metal/oxide interfaces
• Modulation of pure spin currents with a ferromagnetic insulator
• Current-induced spin polarization at the surface of metallic films: a theorem and an ab initio calculation
• Boundary conditions for spin and charge diffusion in the presence of interfacial spin-orbit coupling