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arXiv · 1005.3112

Optical Probing of the Spin Polarization of the nu=5/2 Quantum Hall State

M. Stern·P. Plochocka·V. Umansky·D. K. Maude·M. Potemski·I. Bar-Joseph
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Abstract

We apply polarization resolved photoluminescence spectroscopy to measure the spin polarization of a two dimensional electron gas in perpendicular magnetic field. In the vicinity of filling factor nu=5/2, we observe a sharp discontinuity in the energy of the zero Landau level emission line. We find that the splitting between the two circular polarizations exhibits a sharp drop at nu=5/2 and is equal to the bare Zeeman energy, which resembles the behavior at even filling factors. We show that this behavior is consistent with filling factor nu=5/2 being unpolarized.

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M. Stern, P. Plochocka, V. Umansky, D. K. Maude, M. Potemski, I. Bar-Joseph. 2010-05-18. Optical Probing of the Spin Polarization of the nu=5/2 Quantum Hall State. https://doi.org/10.1103/physrevlett.105.096801

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