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arXiv · 2310.14417

Collective charge excitations between moiré-minibands in twisted WSe2 bilayers from resonant inelastic light scattering

Nihit Saigal·Lennart Klebl·Hendrik Lambers·Sina Bahmanyar·Veljko Antić·Dante M. Kennes·Tim O. Wehling·Ursula Wurstbauer
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Abstract

We establish low-temperature resonant inelastic light scattering (RILS) spectroscopy as a tool to probe the formation of a series of moiré-bands in twisted WSe_{2} bilayers by accessing collective intermoiré-band excitations (IMBE). We observe resonances in RILS spectra at energies in agreement with inter-moiré band transitions obtained from an ab-initio based continuum model. Transitions between the first and second inter-moiré band for a twist angle of about 8° are reported and between first and second, third and higher bands for a twist of about 3°. The signatures from IMBE for the latter highlight a strong departure from parabolic bands with flat minibands exhibiting very high density of states in accord with theory. These observations allow to quantify the transition energies at the K-point where the states relevant for correlation physics are hosted.

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Nihit Saigal, Lennart Klebl, Hendrik Lambers, Sina Bahmanyar, Veljko Antić, Dante M. Kennes, Tim O. Wehling, Ursula Wurstbauer. 2024-06-14. Collective charge excitations between moiré-minibands in twisted WSe2 bilayers from resonant inelastic light scattering. https://arxiv.org/abs/2310.14417

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