Spin transport at finite temperatures: A first-principles study for ferromagnetic$|$nonmagnetic interfaces

Abstract

Symmetry lowering at an interface leads to an enhancement of the effect of spin-orbit coupling and to a discontinuity of spin currents passing through the interface. This discontinuity is characterized by a "spin-memory loss" (SML) parameter $\delta$ that has only been determined directly at low temperatures. Although $\delta$ is believed to be significant in experiments involving interfaces between ferromagnetic and nonmagnetic metals, especially heavy metals like Pt, it is more often than not neglected to avoid introducing too many unknown interface parameters in addition to often poorly known bulk parameters like the spin-flip diffusion length $l_{\mathrm{sf}}$. In this work, we calculate $\delta$ along with the interface resistance $A{R}_{\mathrm{I}}$ and the spin-asymmetry parameter $\gamma$ as a function of temperature for Co$|$Pt and Py$|$Pt interfaces where Py is the ferromagnetic Ni${}_{80}$Fe${}_{20}$ alloy, permalloy. We use first-principles scattering theory to calculate the conductance as well as local charge and spin currents, modeling temperature-induced disorder with frozen thermal lattice and, for ferromagnetic materials, spin disorder within the adiabatic approximation. The bulk and interface parameters are extracted from the spin currents using a Valet-Fert model generalized to include SML.

18 pages, 13 figures

References in corpus (8)

• Direct electronic measurement of the spin Hall effect
• Non-collinear Magnetoelectronics
• Evolution of the spin Hall effect in Pt nanowires: Size and temperature effects
• Interface enhancement of Gilbert damping from first-principles
• Conductance calculations for quantum wires and interfaces: mode matching and Green functions
• Spin-memory loss due to spin-orbit coupling at ferromagnet/heavy-metal interfaces: Ab initio spin-density matrix approach
• Direct Method for Calculating Temperature-Dependent Transport Properties
• Calculating spin transport properties from first principles: spin currents

Cited by in corpus (5)

• Orbital relaxation length from first-principles scattering calculations
• Calculating the spin memory loss at Cu$|$metal interfaces from first principles
• Orbital Hall effect in transition metals from first-principles scattering calculations
• Calculating interface transport parameters at finite temperatures: Nonmagnetic interfaces
• Injection of orbital angular momentum into transition metals from first-principles