Open AccessEvidence of magnetism-induced topological protection in the axion insulator candidate EuSn 2 P 2
Author(s) -
Gian Marco Pierantozzi,
Alessandro De Vita,
Chiara Bigi,
Xin Gui,
Hung-Ju Tien,
Debashis Mondal,
Federico Mazzola,
Jun Fujii,
I. Vobornik,
Giovanni Vinai,
Alessandro Sala,
Cristina Africh,
TienLin Lee,
G. Rossi,
Tay-Rong Chang,
Weiwei Xie,
R. J. Cava,
G. Panaccione
Publication year - 2022
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2116575119
Subject(s) - topological insulator , spintronics , antiferromagnetism , ferromagnetism , topology (electrical circuits) , magnetism , physics , topological order , condensed matter physics , quantum mechanics , mathematics , combinatorics , quantum
Significance Understanding the mutual influence between magnetic and topological properties in a solid system is a fundamental challenge for quantum materials research. The so-called axion insulator is one such case, with exotic properties related to the magnetoelectric effect. In this work, by combining chemical and magnetic-state sensitive electron and X-ray spectroscopies with first-principle calculations we reveal that EuSn2 P2 holds the characteristics of an axion insulator and displays “hidden” electronic properties arising from its layer-dependent ferromagnetic character. As a function of the termination, we observe specific electronic states, holding a spin arrangement representative of a topological insulator. Furthermore, the direction of magnetization enables topological protection, a key property related to axion-based physics.