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Effects of Quantum-Well Inversion Asymmetry on Electron-Nuclear Spin Coupling in the Fractional Quantum Hall Regime

Katsushi Hashimoto·Koji Muraki·Norio Kumada·Tadashi Saku·Yoshiro Hirayama
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Abstract

We examine effects of inversion asymmetry of a GaAs/Al0.3Ga0.7As quantum well (QW) on electron-nuclear spin coupling in the fractional quantum Hall (QH) regime. Increasing the QW potential asymmetry at a fixed Landau-level filling factor (nu) with gate voltages suppresses the current-induced nuclear spin polarization in the nu = 2/3 Ising QH ferromagnet, while it significantly enhances the nuclear spin relaxation at general nu. These findings suggest that mixing of different spin states due to the Rashba spin-orbit interaction strongly affects the electron-nuclear spin coupling.

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Katsushi Hashimoto, Koji Muraki, Norio Kumada, Tadashi Saku, Yoshiro Hirayama. 2004-07-28. Effects of Quantum-Well Inversion Asymmetry on Electron-Nuclear Spin Coupling in the Fractional Quantum Hall Regime. https://doi.org/10.1103/physrevlett.94.146601

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