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Title: Opto-twistronic Hall effect in a three-dimensional spiral lattice
Studies of moiré systems have explained the effect of superlattice modulations on their properties, demonstrating new correlated phases. However, most experimental studies have focused on a few layers in two-dimensional systems. Extending twistronics to three dimensions, in which the twist extends into the third dimension, remains underexplored because of the challenges associated with the manual stacking of layers. Here we study three-dimensional twistronics using a self-assembled twisted spiral superlattice of multilayered WS2. Our findings show an opto-twistronic Hall effect driven by structural chirality and coherence length, modulated by the moiré potential of the spiral superlattice. This is an experimental manifestation of the noncommutative geometry of the system. We observe enhanced light–matter interactions and an altered dependence of the Hall coefficient on photon momentum. Our model suggests contributions from higher-order quantum geometric quantities to this observation, providing opportunities for designing quantum-materials-based optoelectronic lattices with large nonlinearities.  more » « less
Award ID(s):
2323468 2323470 2230240
PAR ID:
10552870
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
nature publishing group
Date Published:
Journal Name:
Nature
Volume:
634
Issue:
8032
ISSN:
0028-0836
Page Range / eLocation ID:
69 to 73
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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