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Magneto-quantum oscillations of the conductance of a tunnel point-contact in the presence of a single defect

Ye. S. Avotina·Yu. A. Kolesnichenko·A. F. Otte·J. M. van Ruitenbeek
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Abstract

The influence of a quantizing magnetic field $H$ to the conductance of a tunnel point contact in the presence of the single defect has been considered. We demonstrate that the conductance exhibits specific magneto-quantum oscillations, the amplitude and period of which depend on the distance between the contact and the defect. We show that a non-monotonic dependence of the point-contact conductance results from a superposition of two types of oscillations: A short period oscillation arising from electron focusing by the field $H$ and a long period oscillation of Aharonov-Bohm-type originated from the magnetic flux passing through the closed trajectories of electrons moving from the contact to the defect and returning back to the contact.

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Ye. S. Avotina, Yu. A. Kolesnichenko, A. F. Otte, J. M. van Ruitenbeek. 2007-03-12. Magneto-quantum oscillations of the conductance of a tunnel point-contact in the presence of a single defect. https://doi.org/10.1103/physrevb.75.125411

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