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From insulator to quantum Hall liquid at low magnetic fields

Tsai-Yu Huang·C. -T. Liang·Gil-Ho Kim·C. F. Huang·Chao-Ping Huang·Jyun-Ying Lin·Hsi-Sheng Goan·D. A. Ritchie
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Abstract

We have performed low-temperature transport measurements on a GaAs two-dimensional electron system at low magnetic fields. Multiple temperature-independent points and accompanying oscillations are observed in the longitudinal resistivity between the low-field insulator and the quantum Hall (QH) liquid. Our results support the existence of an intermediate regime, where the amplitudes of magneto-oscillations can be well described by conventional Shubnikov-de Haas theory, between the low-field insulator and QH liquid.

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Tsai-Yu Huang, C. -T. Liang, Gil-Ho Kim, C. F. Huang, Chao-Ping Huang, Jyun-Ying Lin, Hsi-Sheng Goan, D. A. Ritchie. 2008-09-06. From insulator to quantum Hall liquid at low magnetic fields. https://doi.org/10.1103/physrevb.78.113305

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