Bart van Wees
In recent years it was demonstrated that magnons can be efficient transporters of spins, making new devices and functionalities possible with (insulating) magnonic systems. I will give an introduction into magnon spin transport in ferro/ferri/and anti-ferrro magnetic systems. I will discuss how charge current information can be transformed into (electronic) spin information by the spin Hall effect, which can then generate a magnon spin current in the ferrimagnetic insulators yttrium iron garnet (YIG) [1]. Magnon spins can then be detected via the inverse spin Hall effect, and converted back into a charge signal. These experiments have led to a better understanding of electrically and thermally induced magnon currents (spin Seebeck effect) and emphasize the role of the nonequilibrium magnon chemical potential as the driving force for magnon currents [2] Based on these concepts a magnon transistor geometry was fabricated in which the magnon density was controlled by a magnon injecting gate electrode [3]. It was also shown that magnons in antiferromagnets can effectively transport spins, and experiments demonstrated this in multilayer 2D Van der Waals antiferromagnets[4] I will discuss our recent results on magnon spin caloritronics, including magnon spin Seebeck effect and anomalous Nernst effects, in CrBr3 based ferromagnetic van der Waals systems.
- J. Cornelissen et al., Nat. Phys. 11, 1022 (2015)
- J. Cornelissen et al., Phys. Rev. B94, 014412 (2016)
- J. Cornelissen et al., Phys. Rev. Lett. 120, 097702 (2018)
- Xing et al., Phys. Rev. X9, 011026 (2019)
- Liu et al., Phys. Rev. B 101, 205407 (2020)