Spin-Flip Diffusion Length in 
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mn>5</mml:mn><mml:mi>d</mml:mi></mml:mrow></mml:math>
 Transition Metal Elements: A First-Principles Benchmark

Nair, Rohit Sasidharan; Barati, Ehsan; Gupta, Kriti; Yuan, Zhe; Kelly, Paul J.

doi:10.1103/physrevlett.126.196601

Cited by 14 publications

(15 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…et al [33] for a Au↑|Pt|Au scattering geometry, we obtain l Pt from spin current calculations for temperatures between 100-500 K. The results for l Pt shown in Fig. 5 exhibit a 1/T dependence and, as shown in the inset, satisfy the relationship ρ Pt l Pt = 0.57 ± 0.05 f m 2 [76] in accordance with the Elliott-Yafet mechanism that is based upon free-electron-like energy dispersion [77,78].…”

Section: Spin-flip Diffusion Length L Sf : Ptsupporting

confidence: 71%

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

et al. 2021

Self Cite

View full text Add to dashboard Cite

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 δ that has only been determined directly at low temperatures. Although δ 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 sf . In this work, we calculate δ along with the interface resistance AR I and the spin-asymmetry parameter γ 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.

show abstract

Section: Spin-flip Diffusion Length L Sf : Ptsupporting

confidence: 71%

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

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Pt and Θ Pt should be from our bulk calculations [15,17], we are unable to recover these values from the present calculations for a bulk-like thin film carried out with the same approximations. We identify the boundary condition of (1a) and (1b) used to extract l Pt and Θ Pt from the spin current as the culprit.…”

Section: (Top Panel) Although We Know What Lmentioning

confidence: 55%

“…Recently the magneto-optical Kerr effect (MOKE) was used to probe the spin accumulation in a thin film and thereby estimate Θ sH and l sf without introducing an interface between Pt and another metal [16]. However, the values of Θ sH and l sf extracted from these experiments for Pt are twice those of the best available theoretical estimates using ab-initio calculations [15,17] motivating us to examine the SHE in thin films in more detail.…”

mentioning

confidence: 99%

“…90 layers of this 360=(115+5)×3 supercell were stacked in the z direction and the atoms in the scattering region were displaced at random with a Gaussian distribution of atomic displacements chosen to reproduce the experimental bulk resistivity of ρ = 10.8 µΩ cm [28,29] at room temperature (RT=300K). The thickness of the slab is d ≈ 6 l Pt for a value of l Pt ≡ l Pt sf ≈ 5.2 nm estimated from the decay of a fully polarized spin current injected into Pt [15,17] making it essentially bulk-like. Consistent with this is that at the center of the slab, the spin Hall angle (the ratio of the transverse spin current measured in units of /2 to the longitudinal charge current measured in units of the electron charge −e) is the bulk value, Θ Pt ≡ Θ Pt sH ≈ 4.2% [15].…”

mentioning

confidence: 99%

“…(Top) Spin current j x sy flowing in the x direction at room temperature as a function of x (circles). The green curve results from (1a) using the "bulk" values lPt = 5.2 nm and ΘPt = 4.2% calculated for bulk Pt [15,17]. The grey curve is the best fit using (1a) with lPt = 0.9 nm and ΘPt = 4.0%.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Spin Hall Effect in a Thin Pt Film

Nair,

Rang,

Kelly

2021

Preprint

Self Cite

View full text Add to dashboard Cite

A density-functional-theory based relativistic scattering formalism is used to study charge transport through thin Pt films with room temperature lattice disorder. A Fuchs-Sondheimer specularity coefficient p ∼ 0.5 is needed to describe the suppression of the charge current at the surface even in the absence of surface roughness. The charge current drives a spin Hall current perpendicular to the surface. Analysing the latter with a model that is universally used to interpret the spin Hall effect in thin films and layered materials, we are unable to recover values of the spin-flip diffusion length l sf and spin Hall angle ΘsH that we obtain for bulk Pt using the same approximations. We trace this to the boundary conditions used and develop a generalized model that takes surface effects into account. A reduced value of ΘsH at the surface is then found to describe the first-principles transport results extremely well. The in-plane spin Hall effect is substantially enhanced at the surface.

show abstract

Crossover from Positive to Negative Spin Hall Signal in a Ferromagnetic Metal Induced by the Magnetization Modulated Interface Effect

Zhu

Liu

Zhang

et al. 2023

Advanced Physics Research

Self Cite

View full text Add to dashboard Cite

The spin Hall effect and its inverse (SHE/ISHE), describing the charge‐to‐spin interconversion, are of critical importance to the fundamental physics involving spin‐orbit coupling and the application of spintronic devices. These phenomena in nonmagnetic materials are reasonably understood after extensive studies. In ferromagnetic metals, however, the fundamental issue of generation and transport of pure spin current, especially the interplay of charge‐to‐spin interconversion and magnetization, is as‐yet poorly understood. Here, direct experimental evidence for the sign change in ISHE by injecting a spin current from Y3Fe5O12 into a Fe film via a Cu spacer is reported. The sizable negative ISHE signal (VISHE) in nanometer‐thick Fe films reverses its sign with a comparable magnitude when Fe magnetization is varied from a longitudinal to transverse orientation with respect to spin current polarization. With decreasing Fe thickness, this negative longitudinal VISHE increases rapidly to a larger positive value in magnitude. The opposite spin Hall angles for longitudinally and transversely polarized spin currents are reproduced by first‐principles transport calculations and the sign change is attributed to the anisotropic contribution at the ferromagnetic interface. This work lays a firm foundation for manipulating spin‐to‐charge interconversion with an extra degree of freedom of magnetization orientation through ferromagnetic metals.

show abstract

Spin-Flip Diffusion Length in 5d Transition Metal Elements: A First-Principles Benchmark

Cited by 14 publications

References 55 publications

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

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

Spin Hall Effect in a Thin Pt Film

Crossover from Positive to Negative Spin Hall Signal in a Ferromagnetic Metal Induced by the Magnetization Modulated Interface Effect

Contact Info

Product

Resources

About