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arXiv · 1212.2063

Evidence of inter-layer interaction in magneto-luminescence spectra of electron bilayers

Ilirjan Aliaj·Vittorio Pellegrini·Andrea Gamucci·Biswajit Karmakar·Aron Pinczuk·Loren N. Pfeiffer·Ken W. West
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Abstract

Magneto-luminescence studies in electron bilayers reveal the hallmarks of the even-denominator and other quantum Hall states in the intensities and energies of the inter-band optical recombination lines. In the presence of a small tunneling gap between the layers the magneto-optical emission from the lowest anti-symmetric subband, not populated in a single-electron picture, displays maxima at filling factors 1 and 2/3. These findings uncover a loss of pseudospin polarization, where the pseudospin describes the layer index degree of freedom, that is linked to an anomalous population of the anti-symmetric level due to excitonic correlations. The results demonstrate a new realm to probe the impact of inter-layer Coulomb interaction in quantum Hall bilayers.

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Ilirjan Aliaj, Vittorio Pellegrini, Andrea Gamucci, Biswajit Karmakar, Aron Pinczuk, Loren N. Pfeiffer, Ken W. West. 2012-12-10. Evidence of inter-layer interaction in magneto-luminescence spectra of electron bilayers. https://doi.org/10.1103/physrevb.87.161303

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