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arXiv · 2505.08746

Elevated Hall Responses as Indicators of Edge Reconstruction

Sampurna Karmakar·Amulya Ratnakar·Sourin Das
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Abstract

We investigate edge reconstruction scenarios in the $\nu = 1$ quantum Hall state, focusing on configurations with upstream and downstream charge and neutral modes. Our analysis shows that the coexistence of upstream charge and neutral modes in a multi-terminal geometry can cause pronounced deviations from the expected quantized values of electrical ($e^2/h$) and thermal ($\pi^2 k_\text{B}^{2}T/3h$) Hall conductance dictated by bulk-boundary correspondence. In particular, we find that both electrical and thermal Hall conductances can be significantly enhanced -- exceeding twice their unreconstructed values -- offering a clear diagnostic of edge reconstruction.

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Sampurna Karmakar, Amulya Ratnakar, Sourin Das. 2025-05-13. Elevated Hall Responses as Indicators of Edge Reconstruction. https://doi.org/10.1103/gjjf-w6jx

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