I will present the results of a systematic micromagnetic study of the spin dynamics in magnetic multilayers in the presence of a temperature gradient. In particular, I will describe the flow of magnetisation and energy currents between the layers by means of a general oscillator model, the discrete nonlinear Schrödinger equation (DNLS).
Two new effects are predicted: 1) the rectification of spin-wave (SW) and energy currents: controlling the synchronisation between the spin-oscillators allows to propagate those currents only in one direction. 2) The spin-josepson effect: SW currents is proportional to the sine for the phase differences between spins, in strong analogy will the well known effect
of superconductivity. The DNLS model is very general and those properties are expected to emerge in a large class of systems. In this respect, i will elucidate the strong connection with lattice gauge theories, suggesting possible experiments in system with antisymmetric exchange coupling.
References:
S. Borlenghi et. al., Phys. Rev. Lett. 112, 040703 (2014);
Phys. Rev. E 91, 040102(R) (2015)
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