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arXiv · 2301.07488

Synthesizing $2h/e^2$ resistance plateau at the first Landau level confined in a quantum point contact

M. H. Fauzi·K. Nakagawara·K. Hashimoto·N. Shibata·Y. Hirayama
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Abstract

A comprehensive understanding of quantum Hall edge transmission, especially the hole-conjugate of a Laughlin state such as a $2/3$ state, is critical for advancing fundamental quantum Hall physics and enhancing the design of quantum Hall edge interferometry. In this study, we report a robust intermediate $2h/e^2$ resistance quantization in a quantum point contact (QPC) when the bulk is set at the fractional filling $2/3$ quantum Hall state. Our results suggest the occurrence of two equilibration processes. First, the co-propagating $1/3$ edges moving along a soft QPC arm confining potential fully equilibrate and act as a single $2/3$ edge mode. Second, the $2/3$ edge mode is further equilibrated with an integer $1$ edge mode formed in the QPC. The complete mixing between them results in a diagonal resistance value quantized at $2h/e^2$. Similar processes occur for a bulk filling $5/3$, leading to an intermediate $(2/3)h/e^2$ resistance quantization.

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M. H. Fauzi, K. Nakagawara, K. Hashimoto, N. Shibata, Y. Hirayama. 2023-01-18. Synthesizing $2h/e^2$ resistance plateau at the first Landau level confined in a quantum point contact. https://arxiv.org/abs/2301.07488

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