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arXiv · 2308.08619

Influence of magnetism, strain and pressure on the band topology of EuCd$_2$As$_2$

Adrian Valadkhani·Mikel Iraola·Axel Fünfhaus·Young-Joon Song·Libor Smejkal·Jairo Sinova·Roser Valenti
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Abstract

Motivated by the wealth of proposals and realizations of nontrivial topological phases in EuCd$_2$As$_2$, such as a Weyl semimetallic state and the recently discussed semimetallic versus semiconductor behavior in this system, we analyze in this work the role of the delicate interplay of Eu magnetism, strain and pressure on the realization of such phases. For that we invoke a combination of a group theoretical analysis with ab initio density functional theory calculations and uncover a rich phase diagram with various non-trivial topological phases beyond a Weyl semimetallic state, such as axion and topological crystalline insulating phases, and discuss their realization.

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Adrian Valadkhani, Mikel Iraola, Axel Fünfhaus, Young-Joon Song, Libor Smejkal, Jairo Sinova, Roser Valenti. 2023-08-16. Influence of magnetism, strain and pressure on the band topology of EuCd$_2$As$_2$. https://doi.org/10.1103/physrevb.108.235113

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