Header

UZH-Logo

Maintenance Infos

Tunable Berry Curvature Through Magnetic Phase Competition in a Topological Kagome Magnet


Tsirkin, S S; Neupert, Titus; Guguchia, Z; Verezhak, Joel A T; Gawryluk, D; Yin, J - X; Belopolski, I; Zhou, H; Simutis, G; Zhang, S; Cochran, T A; Chang, G; et al (2019). Tunable Berry Curvature Through Magnetic Phase Competition in a Topological Kagome Magnet. arXiv.org 1904.09353, University of Zurich.

Abstract

Magnetic topological phases of quantum matter are an emerging frontier in physics and material science. Along these lines, several kagome magnets have appeared as the most promising platforms. However, the magnetic nature of these materials in the presence of topological state remains an unsolved issue. Here, we explore magnetic correlations in the kagome magnet Co_3Sn_2S_2. Using muon spin-rotation, we present evidence for competing magnetic orders in the kagome lattice of this compound. Our results show that while the sample exhibits an out-of-plane ferromagnetic ground state, an in-plane antiferromagnetic state appears at temperatures above 90 K, eventually attaining a volume fraction of 80% around 170 K, before reaching a non-magnetic state. Strikingly, the reduction of the anomalous Hall conductivity above 90 K linearly follows the disappearance of the volume fraction of the ferromagnetic state. We further show that the competition of these magnetic phases is tunable through applying either an external magnetic field or hydrostatic pressure. Our results taken together suggest the thermal and quantum tuning of Berry curvature field via external tuning of magnetic order. Our study shows that Co_3Sn_2S_2 is a rare example where the magnetic competition drives the thermodynamic evolution of the Berry curvature field, thus tuning its topological state.

Abstract

Magnetic topological phases of quantum matter are an emerging frontier in physics and material science. Along these lines, several kagome magnets have appeared as the most promising platforms. However, the magnetic nature of these materials in the presence of topological state remains an unsolved issue. Here, we explore magnetic correlations in the kagome magnet Co_3Sn_2S_2. Using muon spin-rotation, we present evidence for competing magnetic orders in the kagome lattice of this compound. Our results show that while the sample exhibits an out-of-plane ferromagnetic ground state, an in-plane antiferromagnetic state appears at temperatures above 90 K, eventually attaining a volume fraction of 80% around 170 K, before reaching a non-magnetic state. Strikingly, the reduction of the anomalous Hall conductivity above 90 K linearly follows the disappearance of the volume fraction of the ferromagnetic state. We further show that the competition of these magnetic phases is tunable through applying either an external magnetic field or hydrostatic pressure. Our results taken together suggest the thermal and quantum tuning of Berry curvature field via external tuning of magnetic order. Our study shows that Co_3Sn_2S_2 is a rare example where the magnetic competition drives the thermodynamic evolution of the Berry curvature field, thus tuning its topological state.

Statistics

Downloads

71 downloads since deposited on 07 Jan 2020
71 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Working Paper
Communities & Collections:07 Faculty of Science > Physics Institute
Dewey Decimal Classification:530 Physics
Language:English
Date:2019
Deposited On:07 Jan 2020 11:14
Last Modified:08 Jan 2020 04:16
Series Name:arXiv.org
ISSN:2331-8422
OA Status:Green
Related URLs:https://arxiv.org/abs/1904.09353

Download

Green Open Access

Download PDF  'Tunable Berry Curvature Through Magnetic Phase Competition in a Topological Kagome Magnet'.
Preview
Content: Published Version
Filetype: PDF
Size: 6MB