Transport Theory for Ferromagnets

Abstract

A quasiclassical transport theory for ferromagnets of large bandwidth is outlined, covering both the ordinary galvanomagnetic effects associated with the Lorentz force and the "spontaneous" effects related specifically to the magnetization. The latter effects are mediated by the spin-orbit interaction and are shown to consist of a scattering-independent Hall effect with no concurrent changes of the longitudinal resistivity, and a Hall effect accompanied by changes of this resistivity and which appears only in the presence of impurity scattering. The manner in which these various effects combine with the usual galvanomagnetic effects is also investigated.

Intrinsic anomalous Hall effect and local polarizabilities

“…We will show that the anomalous Hall conductivity is related to the spatial separation of the mass centers of states with opposite velocities. This confirms the interpretation of AHE in ferromagnetic systems as a consequence of the periodic field of electric dipoles ͑electric polarizability͒ induced by the applied current, 3,10,11 despite the fact that the original arguments were not convincing. 12 We will also show that in nonmagnetic systems, the spin-orbit coupling leads to a periodic variation in the spin polarizability of the current densities in the transport regime.…”

Sign Changes of Intrinsic Spin Hall Effect in Semiconductors and Simple Metals: First-Principles Calculations

“…Such rich sign changes are more than what we can expect from extrinsic scattering mechanism [3]. Two mechanisms, namely, skew scattering and side jump, were mainly discussed in the literature [26]. For a simple discussion, we consider the skew scattering mechanism [26], which dominates over side-jump contribution for the weak disorder limit.…”

“…Two mechanisms, namely, skew scattering and side jump, were mainly discussed in the literature [26]. For a simple discussion, we consider the skew scattering mechanism [26], which dominates over side-jump contribution for the weak disorder limit. In this case, the sign of ESHE depends on the sign of scattering potential [26].…”

Local orbitals approach to the anomalous Hall and Nernst effects in itinerant ferromagnets

“…It is controlled by the real-space distribution of their electron densities [8]. Their different occupation leads to a local charge polarization [9,10]. The corresponding Fermi electron contribution to the orbital momentum can thus be understood as the orbital polarization momentum.…”