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Evolution of the nu = 1 Ground-State in Coupled Double Quantum Wells: Optical Evidence for Broken-Symmetry States

Michael J. Manfra·Justin C. Pniower·Bennett B. Goldberg·Aron Pinczuk·Vittorio Pellegrini·Loren N. Pfeiffer·Ken W. West
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Abstract

We present the first magneto-absorption studies of coupled electron double layers in the quantum Hall regime. Optical absorption spectra in the vicinity of total filling factor nu = 1 reveal intriguing behavior that have no analog in the single electron layer nu = 1 state and demonstrate the interplay between single-particle tunneling and inter-layer Coulomb effects. The spectra provide direct evidence of a ground-state that evolves from a region dominated by single-particle tunneling to a regime in which inter-layer Coulomb interactions determine the nature of the ground-state. Moreover the spectra provide the first direct evidence that the incompressible ground-state at nu = 1 in the many-body regime is not fully pseudospin polarized and is sensitive to the effects of quantum fluctuations in the pseudospin variable.

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Michael J. Manfra, Justin C. Pniower, Bennett B. Goldberg, Aron Pinczuk, Vittorio Pellegrini, Loren N. Pfeiffer, Ken W. West. 1998-09-28. Evolution of the nu = 1 Ground-State in Coupled Double Quantum Wells: Optical Evidence for Broken-Symmetry States. https://arxiv.org/abs/cond-mat/9809373

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