Exciton-polarons in the presence of strongly correlated electronic states in a MoSe$_2$/WSe$_2$ moir\'e superlattice

Aidan J. Campbell; Mauro Brotons-Gisbert; Hyeonjun Baek; Valerio Vitale; Takashi Taniguchi; Kenji Watanabe; Johannes Lischner; Brian D. Gerardot

arXiv · 2202.08879

Exciton-polarons in the presence of strongly correlated electronic states in a MoSe$_2$/WSe$_2$ moir\'e superlattice

Aidan J. Campbell·Mauro Brotons-Gisbert·Hyeonjun Baek·Valerio Vitale·Takashi Taniguchi·Kenji Watanabe·Johannes Lischner·Brian D. Gerardot

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Abstract

Two-dimensional moir\'e materials provide a highly tunable platform to investigate strongly correlated electronic states. Such emergent many-body phenomena can be optically probed in moir\'e systems created by stacking two layers of transition metal dichalcogenide semiconductors: optically injected excitons can interact with itinerant carriers occupying narrow moir\'e bands to form exciton-polarons sensitive to strong correlations. Here, we investigate the behaviour of excitons dressed by a Fermi sea localised by the moir\'e superlattice of a molybdenum diselenide (MoSe$_2$) / tungsten diselenide (WSe$_2$) twisted hetero-bilayer. At a multitude of fractional fillings of the moir\'e lattice, we observe ordering of both electrons and holes into stable correlated electronic states. Magneto-optical measurements reveal extraordinary Zeeman splittings of the exciton-polarons due to exchange interactions in the correlated hole phases, with a maximum close to the correlated state at one hole per site. The temperature dependence of the Zeeman splitting reveals antiferromagnetic ordering of the correlated holes across a wide range of fractional fillings. Our results illustrate the nature of exciton-polarons in the presence of strongly correlated electronic states and reveal the rich potential of the MoSe$_2$/WSe$_2$ platform for investigations of Fermi-Hubbard and Bose-Hubbard physics.

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Aidan J. Campbell, Mauro Brotons-Gisbert, Hyeonjun Baek, Valerio Vitale, Takashi Taniguchi, Kenji Watanabe, Johannes Lischner, Brian D. Gerardot. 2022-02-17. Exciton-polarons in the presence of strongly correlated electronic states in a MoSe$_2$/WSe$_2$ moir\'e superlattice. https://arxiv.org/abs/2202.08879

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