Lawrence Berkeley National Laboratory

Twisted bilayers of van der Waals materials have recently attracted great attention due to their tunable, strongly correlated phenomena. Here, we investigate the chirality-specific physics in three-dimensional moiré superlattices induced by Eshelby twist. Our direct density functional theory calculations reveal helical rotation leads to optical circular dichroism and chirality-specific nonlinear Hall effect, even though there is no magnetization or magnetic field. Both these phenomena can be reversed by changing the structural chirality. This provides a path to constructing chirality-specific materials.