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arXiv · 1705.08523

Probing the fluctuations of the optical properties in time-resolved spectroscopy

Francesco Randi·Martina Esposito·Francesca Giusti·Fulvio Parmigiani·Oleg Misochko·Daniele Fausti·Martin Eckstein
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Abstract

We show that, in optical pump-probe experiments on bulk samples, the statistical distribution of the intensity of ultrashort light pulses after the interaction with a nonequilibrium complex material can be used to measure the time-dependent noise of the current in the system. We illustrate the general arguments for a photo-excited Peierls material. The transient noise spectroscopy allows to measure to what extent electronic degrees of freedom dynamically obey the fluctuation-dissipation theorem, and how well they thermalize during the coherent lattice vibrations. The proposed statistical measurement developed here provides a new general framework to retrieve dynamical information on the excited distributions in nonequilibrium experiments which could be extended to other degrees of freedom of magnetic or vibrational origin.

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Francesco Randi, Martina Esposito, Francesca Giusti, Fulvio Parmigiani, Oleg Misochko, Daniele Fausti, Martin Eckstein. 2017-06-06. Probing the fluctuations of the optical properties in time-resolved spectroscopy. https://doi.org/10.1103/physrevlett.119.187403

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