Spin caloritronics and magnon transport in (anti) ferromagnetic Van der Waals heterostructures*

Spin caloritronics [1] studies an utilizes the coupling between charge, spin and heat transport in a variety of material classes. In recent years it has become clear that magnons (elementary spin wave excitations of the magnetic order) can be excellent long range carriers of spin information in insulating (anti) ferromagnetic materials, thus allowing the transport of spin information, in the absence of charge transport. I will describe how magnons can be generated thermally, by means of the spin Seebeck effect, but also by electrical means, using the spin Hall effect for conversion of charge currents into magnon spin currents (and vice versa). I will then discuss recent experiments [2] [3] [4] where we investigated non-local magnon transport and spin related thermo electric effects such as anomalous Nernst effect to measure non local magnon transport in ferromagnetic (CrBr₃ [2], CrGeTe₃ [2], CrSiTe₃ [3]) and antiferromagnetic (MnPS₃ and related compounds [4]) layered Van der Waals materials. I will conclude by describing the challenges to push the research towards the ultimate 2D magnon regime.
[1] G.E.W. Bauer, E. Saitoh, and B.J. van Wees, Spin Caloritronics, Nat. Mat. 11, 391 (2011)
[2] T. Liu et al., Spin caloritronics in a CrBr₃ based magnetic van der Waals heterostructure, Phys. Rev. B101, 205407 (2020)
[3] D. de Wal, T. Liu et al., in preparation
[4] F. Feringa et al., in preparation