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Phase Transition in ν=2 Bilayer Quantum Hall State

A. Sawada·Z. F. Ezawa·H. Ohno·Y. Horikoshi·Y. Ohno·S. Kishimoto·F. Matsukura·M. Yasumoto·A. Urayama
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Abstract

The Hall-plateau width and the activation energy were measured in the bilayer quantum Hall state at filling factor ν=2, 1 and 2/3, by changing the total electron density and the density ratio in the two quantum wells. Their behavior are remarkably different from one to another. The ν=1 state is found stable over all measured range of the density difference, while the ν=2/3$ state is stable only around the balanced point. The ν=2 state, on the other hand, shows a phase transition between these two types of the states as the electron density is changed.

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A. Sawada, Z. F. Ezawa, H. Ohno, Y. Horikoshi, Y. Ohno, S. Kishimoto, F. Matsukura, M. Yasumoto, A. Urayama. 1998-01-10. Phase Transition in ν=2 Bilayer Quantum Hall State. https://doi.org/10.1103/physrevlett.80.4534

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