Open AccessPressure-induced topological quantum phase transition in the magnetic topological insulator MnBi2Te4
Author(s) -
Wen-Ti Guo,
Lu Huang,
Yue Yang,
Zhigao Huang,
Jianmin Zhang
Publication year - 2021
Publication title -
new journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.584
H-Index - 190
ISSN - 1367-2630
DOI - 10.1088/1367-2630/ac1974
Subject(s) - topological insulator , condensed matter physics , antiferromagnetism , hydrostatic pressure , ferromagnetism , strain engineering , band gap , physics , phase transition , topological order , quantum phase transition , topology (electrical circuits) , phase (matter) , quantum , quantum mechanics , mathematics , combinatorics , thermodynamics
In this paper, topological quantum phase transition was reported in the magnetic topological insulator MnBi 2 Te 4 under pressure strain. Electronic and topological properties of the bulk anti-ferromagnetic MnBi 2 Te 4 were investigated by first-principles calculations. We found that the band structure of MnBi 2 Te 4 changes with the strain, resulting in a phase transition between metal and insulator. From the variation of charge-density distribution with strain, it was found that hydrostatic tensile strain is beneficial for increasing the interlayer spacing, thereby reducing the anti-ferromagnetic interaction between layers. On the contrary, the compressive strain promotes the strengthening of the bonding between the Te and Bi atomic layers. It was worth noting that the phase transition occurs at 2.12% strain when the band crossing is observed at Γ point, suggesting that the band gap has just closed. In addition, through the calculation of surface states, it is observed that, after the action of 2.12% strain, the bulk band gap of the system closes with the surface band gap reopens, achieving an intrinsic mechanism of strain modulation of the MnBi 2 Te 4 antiferromagnetic bulk structure to undergoes a topological quantum phase transition. Our results provide feasible guidance not only for pressure-strain engineering of MnBi 2 Te 4 experimentally but also for developing a meaningful strain-control mechanism for the electronic structures of other potential intrinsic magnetic insulators.