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arXiv · 1503.03051

Fano-Liouville Spectral Signatures in Open Quantum Systems

Daniel Finkelstein-Shapiro·Ines Urdaneta·Monica Calatayud·Osman Atabek·Vladimiro Mujica·Arne Keller
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Abstract

The scattering amplitude from a set of discrete states coupled to a continuum became known as the Fano profile, characteristic for its asymmetric lineshape and originally investigated in the context of photoionization. The generality of the model, and the proliferation of engineered nanostructures with confined states gives immense success to the Fano lineshape, which is invoked whenever an asymmetric lineshape is encountered. However, many of these systems do not conform to the initial model worked out by Fano in that i) they are subject to dissipative processes and ii) the observables are not entirely analogous to the ones measured in the original photoionization experiments. In this letter, we work out the full optical response of a Fano model with dissipation. We find that the exact result for absorption, Raman, Rayleigh and fluorescence emission is a modified Fano profile where the typical lineshape has an additional Lorentzian contribution. Expressions to extract model parameters from a set of relevant observables are given.

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Daniel Finkelstein-Shapiro, Ines Urdaneta, Monica Calatayud, Osman Atabek, Vladimiro Mujica, Arne Keller. 2015-03-10. Fano-Liouville Spectral Signatures in Open Quantum Systems. https://doi.org/10.1103/physrevlett.115.113006

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