The 4th Special CMSM-ERATO Joint Seminar
(The 262nd Special CMSM seminar)


Turning on the heat with spins and their transport across interfaces in heterostructures

Prof. Hari Srikanth

Department of Physics, University of South Florida,
Tampa Florida 33620, USA.

Date & Time: 10:00 - 11:00, December 27th (Wed), 2023.
Place: 1st Conference Room, 1F, Main Bldg., Sengen site.

Abstract:

 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 [1], compensated ferrimagnets [2], topological systems, spin gapless semiconductors [3], 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.

References
[1]“Hybrid magnetic nanoparticles as efficient nanoheaters in biomedical applications” (mini-review) -G.C. Lavorato, R. Das, J. Alonso Masa, M.H. Phan and H. Srikanth, Nanoscale Advances 3, 867 (2021)
[2]“Scaling of the thermally induced sign inversion of longitudinal spin Seebeck effect in a compensated ferrimagnet: role of magnetic anisotropy” -A. Chanda, C. Holzmann, N. Schulz, J. Seyd, M. Albrecht, M.H. Phan and H. Srikanth, Advanced Functional Materials 32, 2109170 (2022)
[3]“Emergence of asymmetric skew-scattering dominated anomalous Nernst effect in spin gapless semiconductors Co1+xFe1-xCrGa” - Amit Chanda, Deepika Rani, Jadupati Nag, Aftab Alam, KG Suresh, Manh-Huong Phan, Hariharan Srikanth, Phys. Rev. B 106, 134416 (2022)

(Contact)

Ken-ichi Uchida, Spin Caloritronics Group
E-mail: UCHIDA.Kenichi[at]nims.go.jp