Moir\'e superlattices formed from transition metal dichalcogenides (TMDs) have been shown to support a variety of quantum electronic phases that are highly tunable using applied electromagnetic fields. While the valley character of the low-energy states dramatically affects optoelectronic properties in the constituent TMDs, this degree of freedom has yet to be fully explored in moir\'e systems. Here, we establish twisted double bilayer WSe2 as an experimental platform to study electronic correlations within Γ-valley moir\'e bands. Through a combination of local and global electronic compressibility measurements, we identify charge-ordered phases at multiple integer and fractional moir\'e band fillings ν. By measuring the magnetic field dependence of their energy gaps and the chemical potential upon doping, we reveal spin-polarized ground states with novel spin polaron quasiparticle excitations. In addition, an applied displacement field allows us to realize a new mechanism of metal-insulator transition at ν=−1 driven by tuning between Γ- and K-valley moir\'e bands. Together, our results demonstrate control over both the spin and valley character of the correlated ground and excited states in this system.
@article{arxiv.2206.10631,
title = {Tunable spin and valley excitations of correlated insulators in $\Gamma$-valley moir\'e bands},
author = {Benjamin A. Foutty and Jiachen Yu and Trithep Devakul and Carlos R. Kometter and Yang Zhang and Kenji Watanabe and Takashi Taniguchi and Liang Fu and Benjamin E. Feldman},
journal= {arXiv preprint arXiv:2206.10631},
year = {2023}
}