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arXiv · 0907.4032

A Phase Diagram for Quantum Hall Bilayers with Strong Inter-layer Correlation

Biswajit Karmakar·Vittorio Pellegrini·Aron Pinczuk·Loren N. Pfeiffer·Ken W. West
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Abstract

Inter-layer excitonic coherence in a quantum Hall bilayer with negligible tunneling is monitored by measurements of low-lying spin excitations. At $ν_T =1$ new quasiparticle excitations are observed above a transition temperature revealing a competing metallic phase. For magnetic fields above an onset Zeeman energy this metallic phase has full spin polarization. A phase diagram in the parameter space of temperature and Zeeman energy reveals that the transition temperature increases at higher fields. This unexpected result suggests intriguing impacts of spin polarization in the highly correlated phases.

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Biswajit Karmakar, Vittorio Pellegrini, Aron Pinczuk, Loren N. Pfeiffer, Ken W. West. 2009-07-23. A Phase Diagram for Quantum Hall Bilayers with Strong Inter-layer Correlation. https://arxiv.org/abs/0907.4032

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