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arXiv · 2503.21314

Symmetry broken states at high displacement fields in ABA trilayer graphene

Simrandeep Kaur·Unmesh Ghorai·Abhisek Samanta·Kenji Watanabe·Takashi Taniguchi·Rajdeep Sensarma·Aveek Bid
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Abstract

In this Letter, we present a comprehensive study of magnetotransport in high-mobility trilayer graphene (TLG) devices under a transverse displacement field, focusing on symmetry-broken Landau levels (LLs) from monolayer-like and bilayer-like bands. A striking displacement-field-induced enhancement of the Land\'e g-factor is observed in the zeroth Landau level of the monolayer-like band, highlighting the role of strong electron-electron interactions. Additionally, we find a rich landscape of LL crossings in the Dirac gully region, accompanied by phase transitions between spin-, gully-, and valley-polarized LLs. These experimental observations are successfully modeled using calculations based on optimized tight-binding parameters. Furthermore, our results reveal significant particle-hole asymmetry in the sequence of LLs in the Dirac gullies, attributed to differing g-factor values for electrons and holes. This asymmetry underscores the limitations of non-interacting models in capturing the complexities of strongly correlated multiband systems. This work provides new insights into the interplay of symmetry-breaking mechanisms and strong correlations in Bernal-stacked trilayer graphene, advancing our understanding of quantum transport phenomena in multiband systems.

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Simrandeep Kaur, Unmesh Ghorai, Abhisek Samanta, Kenji Watanabe, Takashi Taniguchi, Rajdeep Sensarma, Aveek Bid. 2025-03-27. Symmetry broken states at high displacement fields in ABA trilayer graphene. https://arxiv.org/abs/2503.21314

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