Quantum fluctuations in Fr\"ohlich condensate of molecular vibrations driven far from equilibrium

TL;DR

This paper investigates quantum fluctuations in the Fr"ohlich condensate of molecular vibrations driven far from equilibrium, emphasizing the importance of energy redistribution, quantum effects, and potential biological observations.

Contribution

It advances understanding of quantum fluctuations and critical behavior in Fr"ohlich condensates beyond mean field theory, highlighting spectroscopic signatures and biological relevance.

Findings

Energy redistribution is crucial for condensate formation.

Transition from quasi-thermal to super-Poissonian phonon statistics.

Long-lived coherence observed via narrow linewidths.

Abstract

Fr\"ohlich discovered the remarkable condensation of polar vibrations into the lowest frequency mode when the system is pumped externally. For a full understanding of the Fr\"ohlich condensate one needs to go beyond the mean field level to describe critical behavior as well as quantum fluctuations. The energy redistribution among vibrational modes with nonlinearity included is shown to be essential for realizing the condensate and the phonon-number distribution, revealing the transition from quasi-thermal to super-Poissonian statistics with the pump. We further study the spectroscopic properties of the Fr\"ohlich condensate, which are especially revealed by the narrow linewidth. This gives the long-lived coherence and the collective motion of the condensate. Finally we show that the proteins such as Bovine Serum Albumin (BSA) and lysozyme are most likely the candidates for observing such collective modes in THz regime by means of Raman or infrared (IR) spectroscopy.