The additional layer degree of freedom in trilayer moir\'e superlattices of transition metal dichalcogenides enables the emergence of novel excitonic species, such as quadrupolar excitons, which exhibit unique excitonic interactions and hold promise for realizing intriguing excitonic phases and their quantum phase transitions. Concurrently, the presence of strong electronic correlations in moir\'e superlattices, as exemplified by the observations of Mott insulators and generalized Wigner crystals, offers a direct route to manipulate these new excitonic states and resulting collective excitonic phases. Here, we demonstrate that strong exciton-exciton and electron-exciton interactions, both stemming from robust electron correlations, can be harnessed to controllably drive transitions between quadrupolar and dipolar excitons. This is achieved by tuning either the exciton density or electrostatic doping in a trilayer semiconducting moir\'e superlattice. Our findings not only advance the fundamental understanding of quadrupolar excitons but also usher in new avenues for exploring and engineering many-body quantum phenomena through novel correlated excitons in semiconducting moir\'e systems.
@article{arxiv.2508.16009,
title = {Strong Correlation Driven Quadrupolar to Dipolar Exciton Transitions in a Trilayer Moir\'e Superlattice},
author = {Yuze Meng and Lei Ma and Li Yan and Ahmed Khalifa and Dongxue Chen and Shuai Zhang and Rounak Banerjee and Takashi Taniguchi and Kenji Watanabe and Seth Ariel Tongay and Benjamin Hunt and Shi-Zeng Lin and Wang Yao and Yong-Tao Cui and Shubhayu Chatterjee and Su-Fei Shi},
journal= {arXiv preprint arXiv:2508.16009},
year = {2025}
}