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arXiv · 2010.07806

Direct observation of distinct minibands in moiré superlattices

Saien Xie·Brendan D. Faeth·Yanhao Tang·Lizhong Li·Christopher T. Parzyck·Debanjan Chowdhury·Ya-Hui Zhang·Christopher Jozwiak·Aaron Bostwick·Eli Rotenberg·Jie Shan·Kin Fai Mak·Kyle M. Shen
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Abstract

Moiré superlattices comprised of stacked two-dimensional materials present a versatile platform for engineering and investigating new emergent quantum states of matter. At present, the vast majority of investigated systems have long moiré wavelengths, but investigating these effects at shorter, incommensurate wavelengths, and at higher energy scales, remains a challenge. Here, we employ angle-resolved photoemission spectroscopy (ARPES) with sub-micron spatial resolution to investigate a series of different moiré superlattices which span a wide range of wavelengths, from a short moiré wavelength of 0.5 nm for a graphene/WSe2 (g/WSe2) heterostructure, to a much longer wavelength of 8 nm for a WS2/WSe2 heterostructure. We observe the formation of minibands with distinct dispersions formed by the moiré potential in both systems. Finally, we discover that the WS2/WSe2 heterostructure can imprint a surprisingly large moiré potential on a third, separate layer of graphene (g/WS2/WSe2), suggesting a new avenue for engineering moiré superlattices in two-dimensional materials.

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Saien Xie, Brendan D. Faeth, Yanhao Tang, Lizhong Li, Christopher T. Parzyck, Debanjan Chowdhury, Ya-Hui Zhang, Christopher Jozwiak, Aaron Bostwick, Eli Rotenberg, Jie Shan, Kin Fai Mak, Kyle M. Shen. 2020-10-15. Direct observation of distinct minibands in moiré superlattices. https://arxiv.org/abs/2010.07806

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