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تسجيل مستخدم جديدDirect observation of distinct minibands in moire superlattices
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Moire 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 moire 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 moire superlattices which span a wide range of wavelengths, from a short moire 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 moire potential in both systems. Finally, we discover that the WS2/WSe2 heterostructure can imprint a surprisingly large moire potential on a third, separate layer of graphene (g/WS2/WSe2), suggesting a new avenue for engineering moire superlattices in two-dimensional materials.
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