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| 1 | +@Article{Yang_PhysRevB_2024_v110_p235410, |
| 2 | + author = {Shengguo Yang and Jiaxin Chen and Chao-Fei Liu and Mingxing Chen}, |
| 3 | + title = {{Evolution of flat bands in MoSe2/WSe2 moir{\'e} lattices: A study |
| 4 | + combining machine learning and band unfolding methods}}, |
| 5 | + journal = {Phys. Rev. B}, |
| 6 | + year = 2024, |
| 7 | + volume = 110, |
| 8 | + number = 23, |
| 9 | + pages = 235410, |
| 10 | + doi = {10.1103/PhysRevB.110.235410}, |
| 11 | + abstract = {Moir{\textbackslash}'e lattices have served as the ideal quantum |
| 12 | + simulation platform for exploring novel physics due to the flat |
| 13 | + electronic bands resulting from the long wavelength |
| 14 | + moir{\textbackslash}'e potentials. However, the large sizes of this |
| 15 | + type of system challenge the first-principles methods for full |
| 16 | + calculations of their electronic structures, thus bringing |
| 17 | + difficulties in understanding the nature and evolution of the flat |
| 18 | + bands. In this study, we investigate the electronic structures of |
| 19 | + moir{\textbackslash}'e patterns of MoSe{\$}{\_}2{\$}/WSe{\$}{\_}2{\$} |
| 20 | + by combining ab initio and machine learning methods. We find that a |
| 21 | + flat band with a bandwidth of about 5 meV emerges below the valence |
| 22 | + band edge at the K point for the H-stacking at a twist angle of |
| 23 | + 3.89{\$}{\textasciicircum}{\{}{\textbackslash}circ{\}}{\$} without |
| 24 | + spin-orbit coupling effect. Then, it shifts dramatically as the twist |
| 25 | + angle decreases and becomes about 20 meV higher than the valence band |
| 26 | + maximum for the twist angle of |
| 27 | + 3.15{\$}{\textasciicircum}{\{}{\textbackslash}circ{\}}{\$}. Multiple |
| 28 | + ultra-flat bands emerge as the twist angle is reduced to |
| 29 | + 1.7{\$}{\textasciicircum}{\{}{\textbackslash}circ{\}}{\$}. The spin- |
| 30 | + orbit coupling leads to a giant spin splitting comparable to that |
| 31 | + observed in the untwisted system (about 0.45 eV) and is nearly |
| 32 | + independent of twisting and stacking. As a result, the K-valley flat |
| 33 | + band remains the valence band maximum with the inclusion of spin-orbit |
| 34 | + coupling. Band unfolding reveals that the ultra-flat bands formed by |
| 35 | + the {\$}{\textbackslash}Gamma{\$} and K valleys show distinct |
| 36 | + behaviors. The {\$}{\textbackslash}Gamma{\$}-valley flat bands are |
| 37 | + sensitive to the interlayer coupling, thus experiencing dramatic |
| 38 | + changes as the twist angle decreases. In contrast, the K-valley flat |
| 39 | + band, which shows a weak dependence on the interlayer coupling, is |
| 40 | + mainly modulated by structural reconstruction. Therefore, a relatively |
| 41 | + small angle |
| 42 | + (2.13{\$}{\textasciicircum}{\{}{\textbackslash}circ{\}}{\$}) is |
| 43 | + required to generate the K-valley flat band, which experiences a |
| 44 | + transition from the honeycomb to the triangular lattice as the twist |
| 45 | + angle decreases.}, |
| 46 | +} |
| 47 | + |
1 | 48 | @Article{Tang_NatCommun_2024_v15_p8815, |
2 | 49 | author = {Zechen Tang and He Li and Peize Lin and Xiaoxun Gong and Gan Jin and |
3 | 50 | Lixin He and Hong Jiang and Xinguo Ren and Wenhui Duan and Yong Xu}, |
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