TY - JOUR
T1 - Spin transport at finite temperatures
T2 - A first-principles study for ferromagnetic|nonmagnetic interfaces
AU - Gupta, Kriti
AU - Wesselink, Rien J.H.
AU - Yuan, Zhe
AU - Kelly, Paul J.
N1 - Funding Information:
This work was financially supported by the “Nederlandse Organisatie voor Wetenschappelijk Onderzoek” (NWO) through the research programme of the former “Stichting voor Fundamenteel Onderzoek der Materie,” (NWO-I, formerly FOM) and through the use of supercomputer facilities of NWO “Exacte Wetenschappen” (Physical Sciences). K.G. acknowledges funding from the Shell-NWO/FOM “Computational Sciences for Energy Research” PhD program (CSER-PhD; nr. i32; project number 13CSER059) and is grateful to Yi Liu for help in starting this work and to S. Wildeman for helpful discussions. The work was also supported by the Royal Netherlands Academy of Arts and Sciences (KNAW). Work in Beijing was supported by the National Natural Science Foundation of China (Grant No. 61774018), the Recruitment Program of Global Youth Experts, and the Fundamental Research Funds for the Central Universities (Grant No. 2018EYT03).
Publisher Copyright:
© 2021 American Physical Society.
PY - 2021/11/15
Y1 - 2021/11/15
N2 - 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 lsf. In this work, we calculate δ along with the interface resistance ARI and the spin-asymmetry parameter γ as a function of temperature for Co|Pt and Py|Pt interfaces where Py is the ferromagnetic Ni80Fe20 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.
AB - 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 lsf. In this work, we calculate δ along with the interface resistance ARI and the spin-asymmetry parameter γ as a function of temperature for Co|Pt and Py|Pt interfaces where Py is the ferromagnetic Ni80Fe20 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.
UR - http://www.scopus.com/inward/record.url?scp=85120680505&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.104.205426
DO - 10.1103/PhysRevB.104.205426
M3 - Article
AN - SCOPUS:85120680505
VL - 104
JO - Physical review B: Covering condensed matter and materials physics
JF - Physical review B: Covering condensed matter and materials physics
SN - 2469-9950
IS - 20
M1 - 205426
ER -