Seminários

Seminário do grupo de Matéria Condensata Teórica

Título: Chirality-dependent magnon lifetimes in a half-metallic antiferromagnet
Local: antiga sala da biblioteca
Horário: 10h - terça-feira (4/6).

Palestrante: Mariana Odashima (MPI-Halle - Alemanha)

Resumo: By exploring different magnetic orderings one can enhance the functionality of magnonic devices. Recent ultrafast experiments have shown the reversal of the polarity of antiferromagnetic magnons via circularly polarized light [1], and the optical directioning of the spin wave emission in a ferrimagnet [2]. We performed the study of the lifetimes of magnons in the half-Heusler CrMnSb, the prototype of half-metallic antiferromagnets. The unique combination of half-metallicity and magnetic compensation of inequivalent sublattices leads to unexpected properties of the magnon excitations, with strongly different damping properties. We discuss the origin of the unusual magnon properties and a possible way of the engineering of the chirality-dependent attenuation of the magnons.

[1] J. Nishitani, T. Nagashima, and M. Hangyo, Phys. Rev. B 85, 174439 (2012).
[2] T. Satoh et al., Nat. Photon. 6, 662 (2012).

O seminário será proferido em português.