Vendredi 13 janvier 2017 à 14h15
Auditoire Stueckelberg, Ecole de Physique
Topological "spin" hydrodynamics in magnetic insulators
Yaroslav Tserkovnyak, UCLA
New experimental tools have recently emerged that allow us to explore spin transport phenomena in essentially any material, either electrically conducting or insulating. Namely, multiterminal electrical circuits allow for injection of spin currents using the spin Hall effect and detection using the reciprocal process. Similarly, the reciprocal spin Seebeck and Peltier effects can be utilized to inject and detect spin currents thermally. A range of transport regimes for transmitting nonlocal spin signals through insulating media have recently been discussed, with a focus on magnetically-ordered, e.g., ferromagnetic or antiferromagnetic, materials. In this talk, I will review these developments, with a focus on spin superfluidity and related topological aspects, which mitigate the detrimental spin-relaxation processes. In certain cases, the spin transport is entirely superseded by the flow of an emergent topological charge associated with dynamical magnetic textures.