%0 Journal Article %1 PhysRevB.106.125151 %A Jin, Suhua %A Xia, Yunyouyou %A Shi, Wujun %A Hu, Jiayu %A Claessen, Ralph %A Hanke, Werner %A Thomale, Ronny %A Li, Gang %D 2022 %I American Physical Society %J Phys. Rev. B %K a %N 12 %P 125151 %R 10.1103/PhysRevB.106.125151 %T Large-gap quantum anomalous Hall states induced by functionalizing buckled Bi-III monolayer/Al$_2$O$_3$ %U https://link.aps.org/doi/10.1103/PhysRevB.106.125151 %V 106 %X Chiral edge modes inherent to the topological quantum anomalous Hall (QAH) effect are a pivotal topic of contemporary condensed matter research aiming at future quantum technology and application in spintronics. A large topological gap is vital to protecting against thermal fluctuations and thus enabling a higher operating temperature. From first-principles calculations, we propose Al2O3 as an ideal substrate for atomic monolayers consisting of Bi and group-III elements, in which a large-gap quantum spin Hall effect can be realized. Additional half-passivation with nitrogen then suggests a topological phase transition to a large-gap QAH insulator. By effective tight-binding modeling, we demonstrate that Bi-III monolayer/Al2O3 is dominated by px,py orbitals, with subdominant pz orbital contributions. The topological phase transition into the QAH is induced by Zeeman splitting, where the off-diagonal spin exchange does not play a significant role. The effective model analysis promises utility far beyond Bi-III monolayer/Al2O3, as it should generically apply to systems dominated by px,py orbitals with a band inversion at Γ.

@article{PhysRevB.106.125151, abstract = {Chiral edge modes inherent to the topological quantum anomalous Hall (QAH) effect are a pivotal topic of contemporary condensed matter research aiming at future quantum technology and application in spintronics. A large topological gap is vital to protecting against thermal fluctuations and thus enabling a higher operating temperature. From first-principles calculations, we propose Al2O3 as an ideal substrate for atomic monolayers consisting of Bi and group-III elements, in which a large-gap quantum spin Hall effect can be realized. Additional half-passivation with nitrogen then suggests a topological phase transition to a large-gap QAH insulator. By effective tight-binding modeling, we demonstrate that Bi-III monolayer/Al2O3 is dominated by px,py orbitals, with subdominant pz orbital contributions. The topological phase transition into the QAH is induced by Zeeman splitting, where the off-diagonal spin exchange does not play a significant role. The effective model analysis promises utility far beyond Bi-III monolayer/Al2O3, as it should generically apply to systems dominated by px,py orbitals with a band inversion at Γ.}, added-at = {2022-10-11T10:10:43.000+0200}, author = {Jin, Suhua and Xia, Yunyouyou and Shi, Wujun and Hu, Jiayu and Claessen, Ralph and Hanke, Werner and Thomale, Ronny and Li, Gang}, biburl = {https://www.bibsonomy.org/bibtex/2d83b68594c449e4994bbd2d5cd56e972/ctqmat}, day = 29, description = {Phys. Rev. B 106, 125151 (2022) - Large-gap quantum anomalous Hall states induced by functionalizing buckled Bi-III monolayer/${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$}, doi = {10.1103/PhysRevB.106.125151}, interhash = {6d256e8caaa6679481732565c8c7672e}, intrahash = {d83b68594c449e4994bbd2d5cd56e972}, journal = {Phys. Rev. B}, keywords = {a}, month = {09}, number = 12, numpages = {9}, pages = 125151, publisher = {American Physical Society}, timestamp = {2023-10-18T13:35:15.000+0200}, title = {Large-gap quantum anomalous Hall states induced by functionalizing buckled Bi-III monolayer/Al$_{\mathbf{2}}$O$_{\mathbf{3}}$}, url = {https://link.aps.org/doi/10.1103/PhysRevB.106.125151}, volume = 106, year = 2022 }