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arXiv · 2312.04205

Nano-ARPES investigation of twisted bilayer tungsten disulfide

Giovanna Feraco·Oreste De Luca·Przemysław Przybysz·Homayoun Jafari·Oleksandr Zheliuk·Ying Wang·Philip Schädlich·Pavel Dudin·José Avila·Jianting Ye·Thomas Seyller·Paweł Dąbrowski·Paweł Kowalczyk·Jagoda Sławińska·Petra Rudolf·Antonija Grubišić-Čabo
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Abstract

The diverse and intriguing phenomena observed in twisted bilayer systems, such as graphene and transition metal dichalcogenides, prompted new questions about the emergent effects that they may host. However, the practical challenge of realizing these structures on a scale large enough for spectroscopic investigation, remains a significant hurdle, resulting in a scarcity of direct measurements of the electronic band structure of twisted transition metal dichalcogenide bilayers. Here we present a systematic nanoscale angle-resolved photoemission spectroscopy investigation of bulk, single layer, and twisted bilayer WS2 with a small twist angle of 4.4°. The experimental results are compared with theoretical calculations based on density functional theory along the high-symmetry directions Γ-K and Γ-M. Surprisingly, the electronic band structure measurements suggest a structural relaxation occurring at 4.4° twist angle, and formation of large, untwisted bilayer regions.

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Giovanna Feraco, Oreste De Luca, Przemysław Przybysz, Homayoun Jafari, Oleksandr Zheliuk, Ying Wang, Philip Schädlich, Pavel Dudin, José Avila, Jianting Ye, Thomas Seyller, Paweł Dąbrowski, Paweł Kowalczyk, Jagoda Sławińska, Petra Rudolf, Antonija Grubišić-Čabo. 2023-12-07. Nano-ARPES investigation of twisted bilayer tungsten disulfide. https://arxiv.org/abs/2312.04205

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