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arXiv · 2304.03316

Addressing the spin-valley flavors in moir'e mini-bands of MoS2

Chithra H. Sharma·Marta Prada·Jan-Hendrik Schmidt·Isabel Gonz'alez D'iaz-Palacio·Tobias Stauber·Takashi Taniguchi·Kenji Watanabe·Lars Tiemann·Robert H. Blick
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Abstract

The physics of moir'e superlattices and the resulting formation of mini-bands in van der Waals materials have opened up an exciting new field in condensed matter physics. These systems exhibit a rich phase diagram of novel physical phenomena and exotic correlated phases that emerge in the low-dispersing bands. Transition metal dichalcogenides, in particular, molybdenum disulfide (MoS2), are potential candidates to extend the studies on moir'e electronics beyond graphene. Our transport spectroscopy measurements and analysis reveal a correlation-driven phase transition and the emergence of discrete mini-bands in MoS2 moir'e superlattices that remained elusive so far. We resolve these mini-bands arising from quantum mechanical tunneling through Schottky barriers between the MoS2 and its metallic leads. Energy scales deduced from a first approach exhibit an astounding agreement with our experimental observations. The behavior under thermal activation suggests a Lifshitz phase transition at low temperatures that is driven by a complete spin-valley symmetry breaking. These intriguing observations bring out the potential of twisted MoS2 to explore correlated electron states and associated physics.

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Chithra H. Sharma, Marta Prada, Jan-Hendrik Schmidt, Isabel Gonz'alez D'iaz-Palacio, Tobias Stauber, Takashi Taniguchi, Kenji Watanabe, Lars Tiemann, Robert H. Blick. 2023-04-06. Addressing the spin-valley flavors in moir'e mini-bands of MoS2. https://doi.org/10.1103/physrevb.109.195106

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