Spin Resistivity in Magnetic Materials

Abstract

We show in this paper recent results on the spin resistivity in magnetically ordered materials obtained by Monte Carlo simulations. We discuss its behavior as a function of temperature in various types of crystal: ferromagnetic, antiferromagnetic, and frustrated spin systems. In the model used for simulations, we take into account the interaction between itinerant spins and that between lattice spins and itinerant spins. We also include a chemical potential term, as well as an electric eld. We study in particular the behavior of the spin resistivity at and near the magnetic phase transition where the eect of the magnetic ordering is strongest. In ferromagnetic crystals, the spin resistivity shows a sharp peak very similar to the magnetic susceptibility. This can be understood if one relates the spin resistivity to the spinspin correlation as suggested in a number of theories. The dependence of the shape of the peak on physical parameters such as carrier concentration, magnetic eld strength, relaxation time etc. is discussed. In antiferromagnets, the peak is not so pronounced and in some cases it is absent. Its direct relationship to the spinspin correlation is not obvious. As for frustrated spin systems with strong rst-order transition, the spin resistivity shows a discontinuity at the phase transition. To show the eciency of the simulation method, we compare our results with recent experimental data performed on semiconducting MnTe of NiAs structure. We observe a very good agreement with experiments on the spin resistivity in the whole range of temperature.

Exploring quantum Griffiths phase in Ni1−x V x nanoalloys

“…This peak is indicative of the presence of a small nanoparticle volume with uncorrelated PM-like spins, which start getting gradually aligned in the field direction at this temperature and on lowering the temperature further, in line with the observations reported earlier. 21,22…”