TY - JOUR
T1 - Substantial enhancement of thermal spin polarization in Py/Cu interface
AU - Hu, Shaojie
AU - Zhao, Jingyan
AU - Wang, Lei
AU - Cui, Xiaomin
AU - Ohnishi, Kohei
AU - Ariki, Taisei
AU - Min, Tai
AU - Xia, Ke
AU - Kimura, Takashi
N1 - Funding Information:
This work is partially supported by National Key Research Program of China (Grant No. 2017YFA0206200), National Natural Science Foundation for Young Scholar of China (Grant No. 51601139), China Postdoctoral Science Foundation (Grant No. 2017M613101), Grant-in-Aid for Scientific Research on Innovative Areas, Nano Spin Conversion Science (Grant No. 26103002) and that for Scientific Research (A) (No. 18H03866), and JSPS Program for Fostering Globally Talented Researchers. T.M. acknowledges the support from National Key Research Program of China (Grant No. 2016YFA0300702) and Shanxi Province Science and Technology Innovation Project No. 2015ZS-02.
Publisher Copyright:
© 2018 American Physical Society.
Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2018/10/9
Y1 - 2018/10/9
N2 - We investigated the temperature dependence of thermally excited spin current properties of ferromagnet Py (Ni80Fe20) by using a lateral spin-valve structure. The spin-dependent Seebeck coefficient at the Py/Cu interface was found to show a significant increase at low temperature while the charge Seebeck coefficient showed the ordinal reduction with decreasing temperature. This produces a crossover between the charge- and spin-dependent Seebeck coefficients, resulting in the thermal spin polarization greater than 100% below 125 K. From the first-principles calculation specially developed for the Py/Cu interfaces, the spin-dependent Seebeck coefficient is found to be highly susceptible to the magnetic disorder-induced scattering at the interface. The calculation with considering the temperature dependence of the magnetic disorder provides a consistent description for the significant enhancement of spin-dependent Seebeck coefficient in the Py/Cu interface. Our demonstration shows the importance of interface disorder and paves the way toward the development of conventional ferromagnetic metal for the practical application of thermo-spin energy conversion.
AB - We investigated the temperature dependence of thermally excited spin current properties of ferromagnet Py (Ni80Fe20) by using a lateral spin-valve structure. The spin-dependent Seebeck coefficient at the Py/Cu interface was found to show a significant increase at low temperature while the charge Seebeck coefficient showed the ordinal reduction with decreasing temperature. This produces a crossover between the charge- and spin-dependent Seebeck coefficients, resulting in the thermal spin polarization greater than 100% below 125 K. From the first-principles calculation specially developed for the Py/Cu interfaces, the spin-dependent Seebeck coefficient is found to be highly susceptible to the magnetic disorder-induced scattering at the interface. The calculation with considering the temperature dependence of the magnetic disorder provides a consistent description for the significant enhancement of spin-dependent Seebeck coefficient in the Py/Cu interface. Our demonstration shows the importance of interface disorder and paves the way toward the development of conventional ferromagnetic metal for the practical application of thermo-spin energy conversion.
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U2 - 10.1103/PhysRevMaterials.2.104403
DO - 10.1103/PhysRevMaterials.2.104403
M3 - Article
AN - SCOPUS:85059861017
VL - 2
JO - Physical Review Materials
JF - Physical Review Materials
SN - 2475-9953
IS - 10
M1 - 104403
ER -