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Realization of an Interacting Two-Valley AlAs Bilayer System

K. Vakili·Y. P. Shkolnikov·E. Tutuc·E. P. De Poortere·M. Shayegan
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Abstract

By using different widths for two AlAs quantum wells comprising a bilayer system, we force the X-point conduction-band electrons in the two layers to occupy valleys with different Fermi contours, electron effective masses, and g-factors. Since the occupied valleys are at different X-points of the Brillouin zone, the interlayer tunneling is negligibly small despite the close electron layer spacing. We demonstrate the realization of this system via magneto-transport measurements and the observation of a phase-coherent, bilayer $ν$=1 quantum Hall state flanked by a reentrant insulating phase.

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K. Vakili, Y. P. Shkolnikov, E. Tutuc, E. P. De Poortere, M. Shayegan. 2003-09-16. Realization of an Interacting Two-Valley AlAs Bilayer System. https://doi.org/10.1103/physrevlett.92.186404

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