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Fermi-Edge Singularities in the Mesoscopic X-Ray Edge Problem

Martina Hentschel·Denis Ullmo·Harold U. Baranger
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Abstract

We study the x-ray edge problem for a chaotic quantum dot or nanoparticle displaying mesoscopic fluctuations. In the bulk, x-ray physics is known to produce deviations from the naively expected photoabsorption cross section in the form of a peaked or rounded edge. For a coherent system with chaotic dynamics, we find substantial changes and in particular that a photoabsorption cross section showing a rounded edge in the bulk will change to a slightly peaked edge on average as the system size is reduced to a mesoscopic (coherent) scale.

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Martina Hentschel, Denis Ullmo, Harold U. Baranger. 2004-10-28. Fermi-Edge Singularities in the Mesoscopic X-Ray Edge Problem. https://doi.org/10.1103/physrevlett.93.176807

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