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arXiv · 0802.1378

Probing Landau quantisation with the presence of insulator-quantum Hall transition in a GaAs two-dimensional electron system

Kuang Yao Chen·Y. H. Chang·C. -T. Liang·N. Aoki·Y. Ochiai·C. F. Huang·Li-Hung Lin·K. A. Cheng·H. H. Cheng·H. H. Lin·Jau-Yang Wu·Sheng-Di Lin
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Abstract

Magneto-transport measurements are performed on the two-dimensional electron system (2DES) in an AlGaAs/GaAs heterostructure. By increasing the magnetic field perpendicular to the 2DES, magnetoresistivity oscillations due to Landau quantisation can be identified just near the direct insulator-quantum Hall (I-QH) transition. However, different mobilities are obtained from the oscillations and transition point. Our study shows that the direct I-QH transition does not always correspond to the onset of strong localisation.

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Kuang Yao Chen, Y. H. Chang, C. -T. Liang, N. Aoki, Y. Ochiai, C. F. Huang, Li-Hung Lin, K. A. Cheng, H. H. Cheng, H. H. Lin, Jau-Yang Wu, Sheng-Di Lin. 2008-02-11. Probing Landau quantisation with the presence of insulator-quantum Hall transition in a GaAs two-dimensional electron system. https://doi.org/10.1088/0953-8984/20/29/295223

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