ELFT HÍRADÓ

[Szeminárium koordinátor <sem-admin AT szfki.hu>]

SZFI SeminarMasataka KawanoTechnical University of Munich (host: Rózsa 
Levente)Gauge-field picture and thermal Hall effect of magnons in 
antiferromagnetic skyrmion crystalsThursday, 23 May 2024, 13:00, KFKI Campus, 
Bldg. 1, 2nd floor, Conference RoomQuasiparticle excitations in material 
solids often experience a fictitious gauge field, which can be a potential 
source of intriguing transport phenomena. In this study, we show that 
low-energy excitations in insulating antiferromagnetic skyrmion crystals on 
the triangular lattice are effectively described by magnons with an SU(3) 
gauge field [1,2]. The three sublattices in the antiferromagnetic skyrmion 
crystals introduce the three internal degrees of freedom for the magnons, 
which are coupled with their kinetic motion via the SU(3) gauge field 
originating from the combined effect of the topologically nontrivial spin 
texture and local antiferromagnetic couplings. We also demonstrate that the 
non-Abelian nature of the SU(3) gauge field breaks an effective time-reversal 
symmetry and contributes to a magnon thermal Hall effect. Our theory may 
explain the finite thermal Hall conductivity observed in a spinel compound 
MnSc2S4.[1] H. Takeda et al., Nat. Commun. 15, 566 (2024). [2] M. Kawano, 
arXiv:2403.11655 Minden érdeklődőt szívesen látunk! - Everyone is 
welcome to attend.Attila Nagysem-admin AT szfki.hu