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arXiv · 2410.02459

Spin polarization of Quantum Hall states for filling factors 1 < v < 2 measured with microcavity polaritons

Odysseas Williams·Stefan Faelt·Filip Krizek·Werner Wegscheider
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Abstract

Spin polarization measurements were performed in three 2D Electron Gases in GaAs with densities n = 9.1, 7.2 and 6.5 x10^10 cm-2, in the quantum Hall regime. Full spin polarization at v = 1 surrounded by rapid depolarization due to Skyrmion formation was observed in all devices, consistent with past measurements. Depolarization of the v = 4/3, 8/5 states and repolarization of the v = 5/3 state was also measured, in remarkable agreement with a non-interacting, disorder-free Composite Fermion model. Optical power and temperature dependent measurements of the v = 1 state suggest a regime of non-linear optics.

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Odysseas Williams, Stefan Faelt, Filip Krizek, Werner Wegscheider. 2024-10-03. Spin polarization of Quantum Hall states for filling factors 1 < v < 2 measured with microcavity polaritons. https://doi.org/10.1088/1367-2630/adccf0

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