Publication
Title
Quantum anomalous Hall effect in a stable $1T-YN_{2}$ monolayer with a large nontrivial bandgap and a high Chern number
Author
Abstract
 The quantum anomalous Hall (QAH) effect is a topologically nontrivial phase, characterized by a non-zero Chern number defined in the bulk and chiral edge states in the boundary. Using first-principles calculations, we demonstrate the presence of the QAH effect in a 1T-YN2 monolayer, which was recently predicted to be a Dirac half metal without spin-orbit coupling (SOC). We show that the inclusion of SOC opens up a large nontrivial bandgap of nearly 0.1 eV in the electronic band structure. This results in the nontrivial bulk topology, which is confirmed by the calculation of Berry curvature, anomalous Hall conductance and the presence of chiral edge states. Remarkably, a QAH phase of high Chern number C = 3 is found, and there are three corresponding gapless chiral edge states emerging inside the bulk gap. Different substrates are also chosen to study the possible experimental realization of the 1T-YN2 monolayer, while retaining its nontrivial topological properties. Our results open a new avenue in searching for QAH insulators with high temperature and high Chern numbers, which can have nontrivial practical applications.
Language
English
Source (journal)
Nanoscale / Royal Society of Chemistry [London] - Cambridge
Publication
Cambridge : 2018
ISSN
2040-3364
Volume/pages
10 :17 (2018) , p. 8153-8161
ISI
000432261400033
Pubmed ID
29676423
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
 Faculty/Department Research group Project info Publication type Subject Affiliation Publications with a UAntwerp address