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Photoinduced Fano-resonance of coherent phonons in zinc

Muneaki Hase·Jure Demsar·Masahiro Kitajima
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Abstract

Utilizing femtosecond optical pump-probe technique, we have studied transient Fano-resonance in zinc. At high excitation levels the Fourier spectrum of the coherent E$_{2g}$ phonon exhibits strongly asymmetric line shape, which is well modeled by the Fano function. The Fano parameter (1/Q) was found to be strongly excitation fluence dependent while depending weakly on the initial lattice temperature. We attribute the origin of the Fano-resonance to the coupling of coherent phonon to the electronic continuum, with their transition probabilities strongly renormalized in the vicinity of the photoinduced structural transition.

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Muneaki Hase, Jure Demsar, Masahiro Kitajima. 2006-11-02. Photoinduced Fano-resonance of coherent phonons in zinc. https://doi.org/10.1103/physrevb.74.212301

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