Contrasting Γ- and K-Valley Moiré Physics in Twisted Monolayer/Bilayer WSe2
Abstract
Electronic orbital character plays a central role in determining electronic correlations, spin-orbit coupling, dimensionality, and ultimately the quantum phases of condensed-matter systems. Two-dimensional moiré materials have emerged as highly tunable platforms for exploring correlated phenomena, but the role of orbital degrees of freedom remains largely unexplored. Here, we identify twisted monolayer/bilayer WSe2 as a platform in which displacement-field tuning enables moiré physics to be realized in both the K and Γ valleys. The distinct orbital characters of these valleys give rise to contrasting correlated phases at moiré filling factors ν=1 and ν=1/3. At ν=1, the K-valley state is a weak insulator, consistent with an antiferromagnetic state near a van Hove singularity in the intermediate-coupling regime, similar to that observed in twisted bilayer WSe2. In contrast, the Γ-valley state exhibits a pronounced Pomeranchuk effect, consistent with proximity to a Mott transition. At ν=1/3, the K valley hosts a robust generalized Wigner crystal, whereas the Γ-valley state lies near the crystallization boundary and again exhibits a Pomeranchuk effect, with localization enhanced by increasing temperature or magnetic field. Our work highlights the importance of orbital character in defining quantum phases in moiré systems, and identify the Γ valley as a promising platform for exploring correlated phenomena near quantum phase transitions, where competing phases and enhanced fluctuations may give rise to unconventional phases.
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BibTeX
@misc{kuklin2026contrasting,
title = {{Contrasting $Γ$- and K-Valley Moiré Physics in Twisted Monolayer/Bilayer WSe$_2$}},
author = {Jackson Kuklin and Ning Mao and Milan Mandigo-Stoba and Edgar Elias and Tianci Song and Connor Engel and Pola Pietrzkowski and Kenji Watanabe and Takashi Taniguchi and Daniel Rhodes and Yang Zhang and Qianhui Shi},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2607.18212},
eprint = {2607.18212},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2607.18212},
}
RIS
TY - UNPB
TI - Contrasting Γ- and K-Valley Moiré Physics in Twisted Monolayer/Bilayer WSe_2
AU - Jackson Kuklin
AU - Ning Mao
AU - Milan Mandigo-Stoba
AU - Edgar Elias
AU - Tianci Song
AU - Connor Engel
AU - Pola Pietrzkowski
AU - Kenji Watanabe
AU - Takashi Taniguchi
AU - Daniel Rhodes
AU - Yang Zhang
AU - Qianhui Shi
PY - 2026
DA - 2026/10/08
PB - arXiv
DO - 10.48550/arxiv.2607.18212
UR - https://arxiv.org/abs/2607.18212
AB - Electronic orbital character plays a central role in determining electronic correlations, spin-orbit coupling, dimensionality, and ultimately the quantum phases of condensed-matter systems. Two-dimensional moiré materials have emerged as highly tunable platforms for exploring correlated phenomena, but the role of orbital degrees of freedom remains largely unexplored. Here, we identify twisted monolayer/bilayer WSe_2 as a platform in which displacement-field tuning enables moiré physics to be realized in both the K and Γ valleys. The distinct orbital characters of these valleys give rise to contrasting correlated phases at moiré filling factors ν=1 and ν=1/3. At ν=1, the K-valley state is a weak insulator, consistent with an antiferromagnetic state near a van Hove singularity in the intermediate-coupling regime, similar to that observed in twisted bilayer WSe_2. In contrast, the Γ-valley state exhibits a pronounced Pomeranchuk effect, consistent with proximity to a Mott transition. At ν=1/3, the K valley hosts a robust generalized Wigner crystal, whereas the Γ-valley state lies near the crystallization boundary and again exhibits a Pomeranchuk effect, with localization enhanced by increasing temperature or magnetic field. Our work highlights the importance of orbital character in defining quantum phases in moiré systems, and identify the Γ valley as a promising platform for exploring correlated phenomena near quantum phase transitions, where competing phases and enhanced fluctuations may give rise to unconventional phases.
ER -