We demonstrate that two-dimensional Kramers-Weyl fermions can be engineered in spin-orbit coupled twisted bilayers, where the chiral structure of these moir\'e systems breaks all mirror symmetries, confining Kramers-Weyl fermions to high-symmetry points in the Brillouin zone under time reversal symmetry. Our theoretical analysis reveals a symmetry-enforced Weyl-like interlayer moir\'e coupling that universally ensures an ideal radial spin-texture at arbitrary twist angles, under Cnz symmetry with n>2. First principles density functional calculation confirm the realization of these fermions in twisted α-In2Se3 bilayers, where flat bands and out-of-plane ferroelectric polarization in each layer guarantee two-dimensional Kramers-Weyl physics with perfectly ideal radial spin textures.
@article{arxiv.2409.06806,
title = {Moir\'e Kramers-Weyl Fermions from Structural Chirality with Ideal Radial Spin Texture},
author = {D. J. P. de Sousa and Seungjun Lee and Tony Low},
journal= {arXiv preprint arXiv:2409.06806},
year = {2024}
}