Antiferromagnetic domains in a single crystal of the A-type spin-7/2 trigonal topological insulator EuSn$_2$As$_2$

Santanu Pakhira; D. C. Johnston

paper

Antiferromagnetic domains in a single crystal of the A-type spin-7/2 trigonal topological insulator EuSn $_{2}$ As $_{2}$

arXiv:2403.19013

Abstract

EuSn $_{2}$ As $_{2}$ is a trigonal A-type antiferromagnetic topological insulator with the moments aligned in the $ab$ plane and with a Néel temperature $T_{N} = 23.5$ K. Here we report that an EuSn $_{2}$ As $_{2}$ crystal exhibits a broad peak at $H_{c1} = 1100$ Oe in the field derivative $d M_{ab} / d H$ of the $ab$ -plane magnetization $M_{ab} (H)$ at temperature $T = 2$ K, demonstrating the presence of trigonal antiferromagnetic domains. We model these $M_{ab} (H, T = 2 K)$ data and obtain the trigonal anisotropy-energy coefficient $K_{3}$ that is 13.3 and 3.7 times larger than those we previously reported for single crystals of the trigonal compounds EuMg $_{2}$ Sb $_{2}$ and EuMg $_{2}$ Bi $_{2}$ , respectively.

4 pages, 5 captioned figures

Antiferromagnetic domains in a single crystal of the A-type spin-7/2 trigonal topological insulator EuSn2​As2​

Abstract

Antiferromagnetic domains in a single crystal of the A-type spin-7/2 trigonal topological insulator EuSn $_{2}$ As $_{2}$