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arXiv · 2112.11469

Quasiclassical boundary conditions for spin-orbit coupled interfaces with spin-charge conversion

Jacob Linder·Morten Amundsen
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Abstract

The quasiclassical theory of superconductivity provides a methodology to study emergent phenomena in hybrid structures comprised of superconductors interfaced with other materials. A key component in this theory is the boundary condition that the Green functions describing the materials must satisfy. Recently, progress has been made toward formulating such a boundary condition for interfaces with spin-orbit coupling, the latter playing an important role for several phenomena in spintronics. Here, we derive a boundary condition for spin-orbit coupled interfaces that includes gradient terms which enables the description of spin-Hall like effects with superconductors due to such interfaces. As an example, we show that the boundary conditions predict that a supercurrent flowing through a superconductor that is coupled to a normal metal via a spin-orbit interface can induce a non-local magnetization in the normal metal.

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Jacob Linder, Morten Amundsen. 2022-11-08. Quasiclassical boundary conditions for spin-orbit coupled interfaces with spin-charge conversion. https://doi.org/10.1103/physrevb.105.064506

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