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arXiv · 1201.3086

Conductance of a STM contact on the surface of a thin film

N. V. Khotkevych·Yu. A. Kolesnichenko·J. M. van Ruitenbeek
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Abstract

The conductance of a contact, having a radius smaller than the Fermi wave length, on the surface of a thin metal film is investigated theoretically. It is shown that quantization of the electron energy spectrum in the film leads to a step-like dependence of differential conductance G(V) as a function of applied bias eV. The distance between neighboring steps in eV equals the energy level spacing due to size quantization. We demonstrate that a study of G(V) for both signs of the voltage maps the spectrum of energy levels above and below Fermi surface in scanning tunneling experiments.

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N. V. Khotkevych, Yu. A. Kolesnichenko, J. M. van Ruitenbeek. 2012-01-15. Conductance of a STM contact on the surface of a thin film. https://doi.org/10.1063/1.4723673

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