THz probing of non-trivial topological states in Co2MnGe Heusler alloy thin films

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Yadav, Ekta, Nivedan, Anand, Kumar, Sunil
Formato: Preprint
Publicado: 2024
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866914849025425408
author Yadav, Ekta
Nivedan, Anand
Kumar, Sunil
author_facet Yadav, Ekta
Nivedan, Anand
Kumar, Sunil
contents Co2MnGe (CMG) has been demonstrated recently as a half-metallic ferromagnetic Heusler alloy which possesses a topologically non-trivial band structure. This behavior is unique to such systems and hence warrants extensive experimental exploration for potential spintronic and chirality sensitive optoelectonic applications. Here, we demonstrate that an epitaxial thin film of CMG acts as a source of THz radiation upon photoexcitation by optical femtosecond laser pulses. Detailed experiments have revealed that a large contribution to THz emission occurs due to nonmagnetic or spin-independent origin, however, significant contribution in the THz generation is evidenced through excitation light helicity dependent circular photogalvanic effect (CPGE) confirming the presence of topologically non-trivial carriers. Furthermore, we show that not only the topological contribution is easily suppressed but also the overall THz generation efficiency is also affected adversely for the epitaxial films grown at high substrate temperatures.
format Preprint
id arxiv_https___arxiv_org_abs_2403_18332
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle THz probing of non-trivial topological states in Co2MnGe Heusler alloy thin films
Yadav, Ekta
Nivedan, Anand
Kumar, Sunil
Applied Physics
Materials Science
Co2MnGe (CMG) has been demonstrated recently as a half-metallic ferromagnetic Heusler alloy which possesses a topologically non-trivial band structure. This behavior is unique to such systems and hence warrants extensive experimental exploration for potential spintronic and chirality sensitive optoelectonic applications. Here, we demonstrate that an epitaxial thin film of CMG acts as a source of THz radiation upon photoexcitation by optical femtosecond laser pulses. Detailed experiments have revealed that a large contribution to THz emission occurs due to nonmagnetic or spin-independent origin, however, significant contribution in the THz generation is evidenced through excitation light helicity dependent circular photogalvanic effect (CPGE) confirming the presence of topologically non-trivial carriers. Furthermore, we show that not only the topological contribution is easily suppressed but also the overall THz generation efficiency is also affected adversely for the epitaxial films grown at high substrate temperatures.
title THz probing of non-trivial topological states in Co2MnGe Heusler alloy thin films
topic Applied Physics
Materials Science
url https://arxiv.org/abs/2403.18332