Volume 84, Number 3, November 2008
Article Number 34004
Number of page(s) 6
Section Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics
Published online 30 October 2008
EPL, 84 (2008) 34004
DOI: 10.1209/0295-5075/84/34004

Coherence absorption and condensation induced by thermalization of incoherent nonlinear fields

A. Picozzi1 and S. Rica2

1   Institut Carnot de Bourgogne, CNRS, Université de Bourgogne - Dijon, France, EU
2   Laboratoire de Physique Statistique, ENS, CNRS - Paris, France, EU

received 18 April 2008; accepted in final form 30 September 2008; published November 2008
published online 30 October 2008

We show that a conservative system of incoherent nonlinear waves exhibits, as a rule, an irreversible process of coherence transfer, in which the incoherence of the system is absorbed by the small-amplitude field, thus allowing the high-amplitude field to evolve towards a highly condensed coherent state. This process of coherence absorption results from the natural thermalization of the fields to a thermodynamic equilibrium state. The theory reveals that, contrary to a classical gas system, a wave system does not satisfy an equipartition of energy among the particles. Such a distinctive feature is the key property underlying the existence of the coherence absorption process. The coherence absorption effect is shown to also occur in a system of quantum Bose gases.

42.65.Sf - Dynamics of nonlinear optical systems; optical instabilities, optical chaos and complexity, and optical spatio-temporal dynamics.
42.25.Kb - Coherence.
05.45.-a - Nonlinear dynamics and chaos.

© EPLA 2008