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arXiv · 1405.4279

Anomalous Fano Profiles in External Fields

Alejandro Zielinski·Vinay Pramod Majety·Stefan Nagele·Renate Pazourek·Joachim Burgdörfer·Armin Scrinzi
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Abstract

We show that external control of Fano resonances in general leads to complex Fano $q$-parameters. Fano line shapes of photo-electron and transient absorption spectra in presence of an infrared control field are investigated. Computed transient absorption spectra are compatible with a recent experiment [C. Ott {\it et al.}, Science 340, 716 (2013)] but suggest a modification of the interpretation proposed there. Control mechanisms for photo-electron spectra are exposed: control pulses applied {\em during} excitation modify the line shapes by momentum boosts of the continuum electrons. Pulses arriving {\em after} excitation generate interference fringes due to infrared two-photon transitions.

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Alejandro Zielinski, Vinay Pramod Majety, Stefan Nagele, Renate Pazourek, Joachim Burgdörfer, Armin Scrinzi. 2015-06-30. Anomalous Fano Profiles in External Fields. https://doi.org/10.1103/physrevlett.115.243001

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