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arXiv · 1507.04148

Photon number statistics uncover the fluctuations in non-equilibrium lattice dynamics

Martina Esposito·Kelvin Titimbo·Klaus Zimmermann·Francesca Giusti·Francesco Randi·Davide Boschetto·Fulvio Parmigiani·Roberto Floreanini·Fabio Benatti·Daniele Fausti
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Abstract

Fluctuations of the atomic positions are at the core of a large class of unusual material properties ranging from quantum para-electricity to high temperature superconductivity. Their measurement in solids is the subject of an intense scientific debate focused on seeking a methodology capable of establishing a direct link between the variance of the atomic displacements and experimentally measurable observables. Here we address this issue by means of non-equilibrium optical experiments performed in shot-noise limited regime. The variance of the time dependent atomic positions and momenta is directly mapped into the quantum fluctuations of the photon number of the scattered probing light. A fully quantum description of the non-linear interaction between photonic and phononic fields is benchmarked by unveiling the squeezing of thermal phonons in $\alpha$-quartz.

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Martina Esposito, Kelvin Titimbo, Klaus Zimmermann, Francesca Giusti, Francesco Randi, Davide Boschetto, Fulvio Parmigiani, Roberto Floreanini, Fabio Benatti, Daniele Fausti. 2015-07-15. Photon number statistics uncover the fluctuations in non-equilibrium lattice dynamics. https://doi.org/10.1038/ncomms10249

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