Hari Srikanth (Tampa FL, USA): Turning on the heat with spins and their transport across interfaces in heterostructures

Spin-heat coupling is important from a fundamental perspective as well as for many thermoelectric and thermomagnetic applications. Can we generate local heat with magnetic nanoparticles or ‘super spins’? What about manipulation of spin transport using thermal gradients? In this talk, I will provide some insights into these questions based on our research in a number of systems ranging from nanostructures to heterostructures including anisotropic nanoparticles, compensated ferrimagnets, topological systems, spin gapless semiconductors, interfaces of 2D materials like graphene, TMD on ferrites and garnets. The common theme is our ability to sensitively measure and tune the effective interfacial magnetic anisotropy in a large class of magnetic materials including bulk, nanoparticle assemblies and thin film heterostructures. I will describe how we combine conventional and relatively unconventional experimental techniques like magnetometry, RF transverse susceptibility, magnetocaloric effect, anomalous Nernst effect (ANE), spin Seebeck effect (SSE), FMR spin pumping (FMR-SP) to probe the fundamental physics of spin dynamics, spin-heat coupling, thermal spin transport across interfaces. Some recent results on our ongoing projects including core-shell and anisotropic nanoparticles, influence of magnetic anisotropy on spin Seebeck effect (SSE) and anomalous Nernst effect (ANE), universal scaling of SSE in compensated ferrimagnets, estimation of magnon propagation length will be discussed.