Giant nonlinear Hall effect in twisted bilayer WSe₂.

ABSTRACT: The recently discovered nonlinear Hall effect (NHE) in a few non-interacting systems provides a novel mechanism for generating second-harmonic electrical Hall signals under time-reversal-symmetric conditions. Here, we introduce a new approach to engineering an NHE by using twisted moiré structures. We found that the twisted WSe₂ bilayer exhibited an NHE when the Fermi level was tuned to the moiré flat bands. When the first moiré band was half-filled, the nonlinear Hall signal exhibited a sharp peak with a generation efficiency that was at least two orders of magnitude greater than those obtained in previous experiments. We discuss the possible origins of the diverging generation efficiency in twisted WSe₂ based on resistivity measurements, such as moiré-interface-indu

SUBMITTER: Huang M 

PROVIDER: S-EPMC10171643 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature