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

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 ?-quartz.

SUBMITTER: Esposito M

PROVIDER: S-EPMC4703887 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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

Esposito Martina M Titimbo Kelvin K Zimmermann Klaus K Giusti Francesca F Randi Francesco F Boschetto Davide D Parmigiani Fulvio F Floreanini Roberto R Benatti Fabio F Fausti Daniele D

Nature communications 20151222

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 ...[more]

PMID: 26690958

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