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Manifestation of the bulk phase transition in the edge energy spectrum in a two dimensional bilayer electron system

E. V. Deviatov·A. Wurtz·A. Lorke·M. Yu. Melnikov·V. T. Dolgopolov·A. Wixforth·K. L. Campman·A. C. Gossard
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Abstract

We use a quasi-Corbino sample geometry with independent contacts to different edge states in the quantum Hall effect regime to investigate the edge energy spectrum of a bilayer electron system at total filling factor $ν=2$. By analyzing non-linear $I-V$ curves in normal and tilted magnetic fields we conclude that the edge energy spectrum is in a close connection with the bulk one. At the bulk phase transition spin-singlet - canted antiferromagnetic phase $I-V$ curve becomes to be linear, indicating the disappearance or strong narrowing of the $ν=1$ incompressible strip at the edge of the sample.

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E. V. Deviatov, A. Wurtz, A. Lorke, M. Yu. Melnikov, V. T. Dolgopolov, A. Wixforth, K. L. Campman, A. C. Gossard. 2004-02-16. Manifestation of the bulk phase transition in the edge energy spectrum in a two dimensional bilayer electron system. https://doi.org/10.1134/1.1738717

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