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arXiv · 2307.15728

Selective Manipulation and Tunneling Spectroscopy of Broken-Symmetry Quantum Hall States in a Hybrid-edge Quantum Point Contact

Wei Ren·Xi Zhang·Jaden Ma·Xihe Han·Kenji Watanabe·Takashi Taniguchi·Ke Wang
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Abstract

We present a device architecture of hybrid-edge and dual-gated quantum point contact. We demonstrate improved electrostatic control over the separation, position, and coupling of each broken-symmetry compressible strip in graphene. Via low-temperature magneto-transport measurement, we demonstrate selective manipulation over the evolution, hybridization, and transmission of arbitrarily chosen quantum Hall states in the channel. With gate-tunable tunneling spectroscopy, we characterize the energy gap of each symmetry-broken quantum Hall state with high resolution on the order of ~0.1 meV.

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Wei Ren, Xi Zhang, Jaden Ma, Xihe Han, Kenji Watanabe, Takashi Taniguchi, Ke Wang. 2023-07-28. Selective Manipulation and Tunneling Spectroscopy of Broken-Symmetry Quantum Hall States in a Hybrid-edge Quantum Point Contact. https://arxiv.org/abs/2307.15728

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