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Development of the tunnelling gap in disordered 2D electron system with magnetic field: observation of the soft-hard gap transition

Yu. V. Dubrovskii·V. A. Volkov·L. Eaves·E. E. Vdovin·O. N. Makarovskii·J. -C. Portal·M. Henini·G. Hill
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Abstract

Magnetic field suppression of the tunneling between disordered 2D electron systems in GaAs around zero bias voltage has been studied. Magnetic field B normal to the layers induces a dip in the tunneling density of states (TDOS) centered precisely at the Fermi level, i.e. soft tunneling gap. The soft gap has a linear form with finite TDOS diminishing with B at the Fermi level. Driven by magnetic field the transition soft-hard gap has been observed, i.e. the TDOS vanishes in the finite energy window around Fermi level at B>13 T.

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Yu. V. Dubrovskii, V. A. Volkov, L. Eaves, E. E. Vdovin, O. N. Makarovskii, J. -C. Portal, M. Henini, G. Hill. 2005-01-06. Development of the tunnelling gap in disordered 2D electron system with magnetic field: observation of the soft-hard gap transition. https://arxiv.org/abs/cond-mat/0501074

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