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Quantum Coherence of Image-Potential States

P. Wahl·M. A. Schneider·L. Diekhöner·R. Vogelgesang·K. Kern
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Abstract

The quantum dynamics of the two-dimensional image-potential states in front of the Cu(100) surface is measured by scanning tunneling microscopy (STM) and spectroscopy (STS). The dispersion relation and the momentum resolved phase-relaxation time of the first image-potential state are determined from the quantum interference patterns in the local density of states (LDOS) at step edges. It is demonstrated that the tip-induced Stark shift does not affect the motion of the electrons parallel to the surface.

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P. Wahl, M. A. Schneider, L. Diekhöner, R. Vogelgesang, K. Kern. 2003-07-28. Quantum Coherence of Image-Potential States. https://doi.org/10.1103/physrevlett.91.106802

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