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arXiv · 0905.0032

Correlated States of Electrons in Wide Quantum Wells at Low Fillings: The Role of Charge Distribution Symmetry

J. Shabani·T. Gokmen·M. Shayegan
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Abstract

Magneto-transport measurements on electrons confined to a 57 nm-wide, GaAs quantum well reveal that the correlated electron states at low Landau level fillings ($ν$) display a remarkable dependence on the symmetry of the electron charge distribution. At a density of $1.93 \times 10^{11}$ cm$^{-2}$, a developing fractional quantum Hall state is observed at the even-denominator filling $ν= 1/4$ when the distribution is symmetric, but it quickly vanishes when the distribution is made asymmetric. At lower densities, as we make the charge distribution asymmetric, we observe a rapid strengthening of the insulating phases that surround the $ν= 1/5$ fractional quantum Hall state.

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J. Shabani, T. Gokmen, M. Shayegan. 2009-05-01. Correlated States of Electrons in Wide Quantum Wells at Low Fillings: The Role of Charge Distribution Symmetry. https://arxiv.org/abs/0905.0032

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