We propose that flat bands and van Hove singularities near the magic angle can be stabilized against angle disorder in the twisted Kane-Mele model. With continuum model and maximally localized Wannier function approaches, we identify a quadratic dispersion relationship between the bandwidth, interaction parameters versus the twist angle, in contrast to twisted bilayer graphene (TBG). Introducing Kane-Mele spin-orbit coupling to TBG greatly reduces the fractional Chern insulator indicator and enhances the stability of fractional Chern states near the magic angle, as confirmed by exact diagonalization calculations. Moreover, in twisted bilayer Pt2HgSe3 with intrinsic Kane-Mele spin-orbit coupling, we identify a topological flat band at a large twist angle around 4 degrees.
@article{arxiv.2408.06866,
title = {Stable magic angle in twisted Kane-Mele materials},
author = {Cheng Xu and Yong Xu and Wenhui Duan and Yang Zhang},
journal= {arXiv preprint arXiv:2408.06866},
year = {2024}
}
Comments
5+6 pages, 4+2 figures, the label in Fig. 3 has been corrected