Bilayer Excitons in the Laughlin Fractional Quantum Hall State

Ron Q. Nguyen; Naiyuan J. Zhang; Navketan Khurana-Batra; Sarah Alkidim; Xiaoxue Liu; Kenji Watanabe; Takashi Taniguchi; D. E. Feldman; J. I. A. Li

arXiv · 2410.24208

Bilayer Excitons in the Laughlin Fractional Quantum Hall State

Ron Q. Nguyen·Naiyuan J. Zhang·Navketan Khurana-Batra·Sarah Alkidim·Xiaoxue Liu·Kenji Watanabe·Takashi Taniguchi·D. E. Feldman·J. I. A. Li

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Abstract

The Laughlin state embodies a universal class of fractional quantum Hall effects arising in two-dimensional electron systems subjected to strong perpendicular magnetic fields. Conventionally described by a single-component wavefunction, the Laughlin state features fractionally charged quasiparticles arising from correlations within one electron species. Here, we explore a novel physical situation by introducing inter-species Coulomb coupling between two intra-species Laughlin states in a quantum Hall graphene bilayer structure. Although quasiparticle excitations typically exhibit charge gaps of tens of Kelvin, we observe that this energy scale is significantly lowered through interlayer excitonic pairing between quasiparticles and quasiholes. Identified via transport measurements, these excitons belong to an unprecedented category of charge-neutral anyons, opening a new avenue for investigating exotic quantum statistics and phases of matter.

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Ron Q. Nguyen, Naiyuan J. Zhang, Navketan Khurana-Batra, Sarah Alkidim, Xiaoxue Liu, Kenji Watanabe, Takashi Taniguchi, D. E. Feldman, J. I. A. Li. 2024-10-31. Bilayer Excitons in the Laughlin Fractional Quantum Hall State. https://arxiv.org/abs/2410.24208

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