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Metamorphosis of a Quantum Hall Bilayer State into a Composite Fermion Metal

Biswajit Karmakar·Stefano Luin·Vittorio Pellegrini·Aron Pinczuk·Brian S. Dennis·Loren N. Pfeiffer·Ken W. West
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Abstract

Composite fermion metal states emerge in quantum Hall bilayers at total Landau level filling factor $ν_T$=1 when the tunneling gap collapses by application of in-plane components of the external magnetic field. Evidence of this transformation is found in the continua of spin excitations observed by inelastic light scattering below the spin-wave mode at the Zeeman energy. The low-lying spin modes are interpreted as quasiparticle excitations with simultaneous changes in spin orientation and composite fermion Landau level index.

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Biswajit Karmakar, Stefano Luin, Vittorio Pellegrini, Aron Pinczuk, Brian S. Dennis, Loren N. Pfeiffer, Ken W. West. 2007-02-13. Metamorphosis of a Quantum Hall Bilayer State into a Composite Fermion Metal. https://doi.org/10.1016/j.ssc.2007.07.005

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