Electrical transport with temperature-induced spin disorder in NiMnSb

Autor:	Ilja Turek, Karel Carva, D. Wagenknecht, Libor Šmejkal, Josef Kudrnovský
Rok vydání:	2019
Předmět:	Condensed Matter::Materials Science Materials science Spin polarization Condensed matter physics Electrical resistivity and conductivity Phonon Impurity Magnon Coherent potential approximation Curie temperature Condensed Matter Physics Spin (physics) Electronic Optical and Magnetic Materials
Zdroj:	Journal of Magnetism and Magnetic Materials. 474:517-521
ISSN:	0304-8853
DOI:	10.1016/j.jmmm.2018.11.047
Popis:	We investigate theoretically the combined effect of phonons and magnons caused by finite temperatures on the electrical resistivity of nonstoichiometric half-Heusler NiMnSb alloy. The coherent potential approximation within the alloy analogy model is employed for an efficient treatment of chemical impurities, atomic displacements, and magnetic disorder. Spin fluctuations of local Mn moments are described by two models: (i) uncompensated disordered local moment approach and (ii) tilting of the moments. The calculated resistivity agrees with experimental data, the agreement is good up to 600 K. We show that a strong magnetic disorder leads to a violation of the Matthiessen’s rule for the resistivity. We also discuss the spin polarization of the electrical current which exceeds 90% at room temperature but it is dramatically reduced by the magnetic disorder for higher temperatures approaching the Curie point ( T C = 730 K).
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::6e5e9d224350da4d83b2a24e0a1d1ca6 https://doi.org/10.1016/j.jmmm.2018.11.047 Zobrazit plný text záznamu Full Text from ScienceDirect