The disordered local moment approach to the spin-disorder resistivity of metallic ferromagnets

Abstract

Abstract. The spin-disorder resistivity (SDR) of transition metal ferromagnets (Fe, Co, Ni), rare-earth ferromagnet Gd, and Ni 2 MnSn Heusler alloy is determined from first principles. We identify the SDR at the Curie temperature with the residual resistivity of the corresponding system evaluated in the framework of the disordered local moment (DLM) model which has the zero spin-spin correlation function. The underlying electronic structure is determined in the framework of the tight-binding linear muffin-tin orbital method which employs the coherent potential approximation (CPA) to describe the DLM state. The DLM fixed-spin moment approach is used in the case when the DLM moment collapses. The electronic structure of hcp-Gd is determined using both the open core and LDA+U approaches. The Kubo-Greenwood approach is used to estimate the resistivity. For bcc-Fe and Ni 2 MnSn alloy we shall also estimate the temperature-dependent of resistivity below the Curie temperature using a semiempirical approach. Calculations are compared with the supercell Landauer-Büttiker approach developed recently as well as with available experimental data and overall good agreement is obtained.

High‐Efficiency Spin–Orbit Torque Switching Using a Single Heavy‐Metal Alloy with Opposite Spin Hall Angles

“…Theoretical studies have shown that the resistivity (ρ) in normal metals and alloys contains two dominant mechanisms, namely, the scattering of conduction electrons on impurities and other structural defects. [ 43–45 ] In our work, the gradual increase in the Pt 1‐x Gd x alloy compositions can be viewed as strong interface modification. With a much larger atomic radius of Gd (0.97 Å) than that of the Pt (0.63 Å), the replacement of Gd to Pt will result in an increase in lattice constant, which will modify the interface morphology.…”

Effect of the temperature and magnetic field induced martensitic transformation in bulk Fe$_{45}$Mn$_{26}$Ga$_{29}$ alloy on its electronic structure and physical properties

“…Indeed, electron-magnon (spindisorder) scattering usually reaches its maximum near the Curie temperature; above T C the spin-disorder mechanism is independent of T . Therefore, for some ferromagnetic metals and alloys (including FM HA), a distinct change in the slope of the ρ(T ) dependence can be expected at T C [20,21,22,23].…”

Effect of Crystal Structure on Transport and Magnetic Properties of Bulk Ni$_{2}$MnSn Heusler Alloys

“…Зазвичай електрон-магнонний внесок в результуючий електроопір феромагнітного металу досягає свого максимуму біля температури Кюрі Т С , а вище Т С він вже не залежить від температури. Отже, для феромагнітних металів та стопів біля Т С на температурній залежності (Т) має спостерігатися, принаймні, зміна величини ТКЕ [24,25]. Існує декілька можливих механізмів появи неґативного ТКЕ в металах та стопах.…”