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Hybridization of electron subbands in a double quantum well at quantizing magnetic field

V. T. Dolgopolov·A. A. Shashkin·E. V. Deviatov·F. Hastreiter·M. Hartung·A. Wixforth·K. L. Campman·A. C. Gossard
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Abstract

We employ magnetocapacitance and far-infrared spectroscopy techniques to study the spectrum of the double-layer electron system in a parabolic quantum well with a narrow tunnel barrier in the centre. For gate-bias-controlled asymmetric electron density distributions in this soft two-subband system we observe both individual subband gaps and double layer gaps at integer filling factor $ν$. The bilayer gaps are shown to be either trivial common for two subbands or caused by hybridization of electron subbands in magnetic field. We describe the observed hybrid gaps at $ν=1$ and $ν=2$ within a simple model for the modified bilayer spectrum.

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V. T. Dolgopolov, A. A. Shashkin, E. V. Deviatov, F. Hastreiter, M. Hartung, A. Wixforth, K. L. Campman, A. C. Gossard. 1998-06-17. Hybridization of electron subbands in a double quantum well at quantizing magnetic field. https://doi.org/10.1103/physrevb.59.13235

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