Moiré-induced structural frustration
ORAL
Abstract
We theoretically show that lattice relaxation of moiré materials can induce frustration as well as novel spontaneous symmetry breaking at a purely structural level. In particular, the domain wall junctions in relaxed moiré materials spontaneously develop twirl distortions. We show that in lattice-mismatched heterobilayers, the chiralities of neighboring twirls prefer anti-alignment, forming staggered patterns that are well described by Ising-like antiferromagnetic lattice φ4 theories. In moiré systems with triangular domains, this leads to frustration in the chirality configuration of the structural twirls and to hysteresis with respect to variation of the average twist angle and possibly also other more convenient control parameters. We discuss the influence of structural frustration on electronic properties of moiré materials, and propose that structural frustration will enrich the broad family of exotic phases that have been discovered in moiré materials.
*We acknowledge computational resources provided by the Texas Advanced Computing Center (TACC). J.S. and I.M. acknowledge support by the US Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. G.C. acknowledges support from Engineering and Physical Sciences Research Council (EPSRC) grant EP/V062654/1 and support by grant NSF PHY-2309135 to the Kavli Institute for Theoretical Physics during the initial part of this work.
–
Publication: J. Shi, G. Chaudhary, A. H. MacDonald, and I. Martin, "Spontaneous Twirls and Structural Frustration in Moiré Materials", arXiv:2509.10907 (https://arxiv.org/abs/2509.10907)
Presenters
-
Jingtian Shi
- Argonne National Laboratory