Download file (16.8 MB)
Download as zip (16.6 MB)

Collection

Citation

Description:

Field-effect devices constructed from van der Waals (vdW) materials with hexagonal boron nitride (hBN) as gate dielectrics usually exhibit negligible hysteresis, enabling exquisitely detailed studies of diverse gate-voltage-tuned phenomena. Recently, a dramatic hysteresis effect, sometimes called the “gate doesn’t work” or “electron ratchet” effect, has been observed sporadically in otherwise typical vdW devices. Its lack of reproducibility has hindered clear identification of its origin, which has been postulated to rely on the combination of bilayer graphene with moiré patterns from rotationally aligned hBN. Here, we report observing this effect in devices with thicker graphite channels, associating it with a single graphite surface. Remarkably, the hysteresis persists at room temperature, without intentional hBN alignment, and even with a WSe2 monolayer inserted between the graphite and hBN. Furthermore, it exhibits continuous relaxation over long time scales. These observations impose strong constraints on the origin of this puzzling phenomenon, which has exciting potential applications if it can be mastered.

Rights:

• In Copyright
  

  This document is the Accepted Manuscript version of a Published Article that appeared in final form in Nano Letters, copyright © 2025 American Chemical Society. To access the final published article, see https://doi.org/10.1021/acs.nanolett.5c01799.

Keyword: van der Waals materials, Hysteresis, Hexagonal boron nitride (hBN)

Date published: 2025-05-28

Publisher: American Chemical Society (ACS)

Journal:

• Nano Letters (ISSN: 15306984) vol. 25 issue. 21 p. 8768-8774

Funding:

• Idaho National Laboratory 23-4683
• Ministry of Education, Culture, Sports, Science and Technology
• Intelligence Community Postdoctoral Research Fellowship Program
• Clean Energy Institute
• Office of the Director of National Intelligence
• Office of Naval Research N00014-22-1-2582
• Japan Society for the Promotion of Science 21H05233
• Japan Society for the Promotion of Science 23H02052
• U.S. Department of Energy
• National Science Foundation 2308979
• National Science Foundation DMR-2041972

Manuscript type: Author's version (Accepted manuscript)

MDR DOI:

First published URL: https://doi.org/10.1021/acs.nanolett.5c01799

Related item:

Other identifier(s):

Contact agent:

Updated at: 2026-08-05 10:00:53 +0900

Published on MDR: 2026-08-05 12:30:57 +0900