Purely anharmonic charge-density wave in the 2D Dirac semimetal SnP

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Gutierrez-Amigo, Martin, Yuan, Fang, Campi, Davide, Schoop, Leslie M., Vergniory, Maia G., Errea, Ion
Natura: Preprint
Pubblicazione: 2023
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866914563739353088
author Gutierrez-Amigo, Martin
Yuan, Fang
Campi, Davide
Schoop, Leslie M.
Vergniory, Maia G.
Errea, Ion
author_facet Gutierrez-Amigo, Martin
Yuan, Fang
Campi, Davide
Schoop, Leslie M.
Vergniory, Maia G.
Errea, Ion
contents Charge density waves (CDWs) in two-dimensional (2D) materials have been a major focus of research in condensed matter physics for several decades due to their potential for quantum-based technologies. In particular, CDWs can induce a metal-insulator transition by coupling two Dirac fermions, resulting in the emergence of a topological phase. Following this idea, here we explore the behavior of three different CDWs in a new 2D layered material, SnP, using both density functional theory calculations and experimental synthesis to study its stability. The layered structure of its bulk counterpart, Sn4P3, suggests that the structure can be synthesized down to the monolayer by exfoliation or chemical means. However, despite the stability of the bulk, the monolayer shows unstable phonons at Γ, K, and M points of the Brillouin zone, which lead to three possible charge-density-wave phases. All three CDWs lead to metastable insulating phases, with the one driven by the the active phonon in the K point being topologically non-trivial under strain. Strikingly, the ground-state structure is only revealed due to the presence of strong anharmonic effects. This, underscores the importance of studying CDWs beyond the conventional harmonic picture, where the system's ground state can be elucidated solely from the harmonic phonon spectra.
format Preprint
id arxiv_https___arxiv_org_abs_2309_05847
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Purely anharmonic charge-density wave in the 2D Dirac semimetal SnP
Gutierrez-Amigo, Martin
Yuan, Fang
Campi, Davide
Schoop, Leslie M.
Vergniory, Maia G.
Errea, Ion
Materials Science
Charge density waves (CDWs) in two-dimensional (2D) materials have been a major focus of research in condensed matter physics for several decades due to their potential for quantum-based technologies. In particular, CDWs can induce a metal-insulator transition by coupling two Dirac fermions, resulting in the emergence of a topological phase. Following this idea, here we explore the behavior of three different CDWs in a new 2D layered material, SnP, using both density functional theory calculations and experimental synthesis to study its stability. The layered structure of its bulk counterpart, Sn4P3, suggests that the structure can be synthesized down to the monolayer by exfoliation or chemical means. However, despite the stability of the bulk, the monolayer shows unstable phonons at Γ, K, and M points of the Brillouin zone, which lead to three possible charge-density-wave phases. All three CDWs lead to metastable insulating phases, with the one driven by the the active phonon in the K point being topologically non-trivial under strain. Strikingly, the ground-state structure is only revealed due to the presence of strong anharmonic effects. This, underscores the importance of studying CDWs beyond the conventional harmonic picture, where the system's ground state can be elucidated solely from the harmonic phonon spectra.
title Purely anharmonic charge-density wave in the 2D Dirac semimetal SnP
topic Materials Science
url https://arxiv.org/abs/2309.05847