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

Cristina Sanz-Fernández; Van Tuong Pham; Edurne Sagasta; Luis E. Hueso; Ilya V. Tokatly; Fèlix Casanova; F. Sebastián Bergeret

arXiv · 2007.01596

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

Cristina Sanz-Fernández·Van Tuong Pham·Edurne Sagasta·Luis E. Hueso·Ilya V. Tokatly·Fèlix Casanova·F. Sebastián Bergeret

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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 $σ_{\rm{sc/cs}}$. 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.

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Cristina Sanz-Fernández, Van Tuong Pham, Edurne Sagasta, Luis E. Hueso, Ilya V. Tokatly, Fèlix Casanova, F. Sebastián Bergeret. 2020-07-03. Quantification of interfacial spin-charge conversion in metal/insulator hybrid structures by generalized boundary conditions. https://arxiv.org/abs/2007.01596

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