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arXiv · 1106.5605

Insulating phase of a two-dimensional electron gas in MgZnO/ZnO heterostructure below nu = 1/3

Y. Kozuka·A. Tsukazaki·D. Maryenko·J. Falson·S. Akasaka·K. Nakahara·S. Nakamura·S. Awaji·K. Ueno·M. Kawasaki
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Abstract

We report magnetotransport properties of a two-dimensional electron gas confined at MgZnO/ZnO heterointerface in a high magnetic field up to 26 T. High electron mobility and low charge carrier density enabled the observation of the fractional quantum Hall state nu = 1/3. For an even lower charge carrier density, we observe a transition from quantum Hall liquid to an insulator below the filling factor 1/3. Because of the large electron effective mass in ZnO, we suggest the MgZnO/ZnO heterostructure to be a prototype system for highly correlated quantum Hall physics.

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Y. Kozuka, A. Tsukazaki, D. Maryenko, J. Falson, S. Akasaka, K. Nakahara, S. Nakamura, S. Awaji, K. Ueno, M. Kawasaki. 2011-06-28. Insulating phase of a two-dimensional electron gas in MgZnO/ZnO heterostructure below nu = 1/3. https://doi.org/10.1103/physrevb.84.033304

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