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arXiv · 2411.16060

Spin dynamics of a quasi-one-dimensional electron in the quantum limit

M. H. Fauzi·M. Takahashi·T. Aono·K. Hashimoto·Y. Hirayama
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Abstract

We study electron spin dynamics whose movement is restricted to the lowest one dimensional subband channel ($G \le 2e^2/h $), through nuclear spin relaxation rate measurement ($1/T_1$). We observe an unusual double-peak structure in the $1/T_1$ profile below the lowest subband level, where the up and down spin edge channel is still largely overlap. This profile significantly deviates from the behavior predicted by a non-interacting electron model, in which the only source of relaxation is through thermal fluctuations near the Fermi level. Our experimental results, supported by theoretical calculations, suggest that enhanced electron-electron interactions at the center of a quantum point contact are the likely origin of the observed double-peak structures.

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M. H. Fauzi, M. Takahashi, T. Aono, K. Hashimoto, Y. Hirayama. 2024-11-26. Spin dynamics of a quasi-one-dimensional electron in the quantum limit. https://arxiv.org/abs/2411.16060

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