Determination of the magnetic order in the EuIn<sub>2</sub>As<sub>2</sub>, an axion insulator candidate
ORAL
Abstract
EuIn2As2 is a Zintl compound recently reported as a possible first example of axion insulator with antiferromagnetic (AF) long-range order and characteristic colossal negative magnetoresistance. It thus represents a unique platform to investigate the physics of axion insulators and, in particular, to focus on the interplay between the AF order and the topologically protected features of the electronic band structure. Here, we present results from single-crystal magnetic diffraction experiments. Surprisingly, our results reveal the successive stabilization of two different sets of magnetic Bragg reflections indexed with the propagation vectors k1=(0,0,0.31) and k2=(0,0,0) below TN1=17 and TN2=15 K, respectively, despite the chemical unit cell containing only a single Eu site. The two magnetic structures are believed to coexist at T≤TN2, and were individually determined from refinement analyses. We will describe both magnetic structures and discuss the influence of our results upon the current understanding of the material’s topological features.
*Work supported by the Center for the Advancement of Topological Semimetals, an Energy Frontier Research Center funded by the U.S. DOE Office of Science, Office of BES, through Ames Laboratory under its Contract No. DE-AC02-07CH11358.
–
Presenters
-
Simon Riberolles
- Ames Laboratory, Ames, IA 50011, USA
- Division of Materials Science & Engineering, Ames Laboratory