Magnetism has a significant effect on electron transport phenomena. A classic example is the anomalous Hall effect, where the magnetism produces a Hall current proportional to the ferromagnetic moment. The studies on magnetism-related transport phenomena have mostly focused on two cases. The first is the low-temperature magnetically-ordered phase, in which the deformation of the electronic band and electron-magnon scattering are dominant. Another is the high-temperature paramagnetic phase, where the effect of magnetic moments is well described as the scattering by a single magnetic impurity. In contrast, recent experiments find unique transport phenomena at an intermediate temperature comparable to the magnetic transition temperature. In this talk, I discuss the magnetic scattering by two- and three-spin clusters, which gives the leading order correction to the magnetic scattering theory in the high-temperature limit. These corrections contribute to the electron transport in the intermediate temperature where the short-range magnetic correlation develops. We find that the spin correlation in the spin cluster brings about various asymmetric scattering. The asymmetric scatterings produce various transport phenomena such as extrinsic-type anomalous Hall effect and nonreciprocal current. These results are consistent with recent experiments and suggest a new direction in realizing a large anomalous Hall effect and nonreciprocal response.

Chair: Gil Young Cho

This event is jointly organized by the Korea Institute for Advanced Study and the University of Tokyo. “Correlated Electrons Virtual International Seminars (CEVIS)”　https://sites.google.com/view/cevis2020/home