Heidelberg 2015 – wissenschaftliches Programm
Q 51.4: Vortrag
Donnerstag, 26. März 2015, 12:00–12:15, P/H2
Mean-Field Analysis of Selforganization of Atoms in Cavities — •Simon Jäger, Stefan Schütz, and Giovanna Morigi — Theoretische Physik, Universität des Saarlandes, D-66123 Saarbrücken, Germany
Atoms can spontaneously form spatially ordered structures in optical resonators when they are transversally driven by lasers. This occurs by means of photon-mediated long-range forces, which establish correlations when the intracavity photon number exceeds a threshold value. The selforganization transition is an out-of-equilibrium phenomenon, where losses are an essential element determining the threshold behaviour . In this contribution, we analyse the nature of the transition by means of a mean-field Fokker-Planck equation (FPE), which has been systematically derived from the master equation of atoms and cavity field and describes the dynamics of the one-particle density matrix. This FPE has the form of a Vlaslov equation when retardation effects, giving rise to noise, are neglected . We analyse the dynamics of the order parameter, which quantifies the localization of the atoms in ordered patterns, and show that close to the selforganization threshold its dynamics is determined by a potential of Landau form in an appropriately defined thermodynamic limit. We then perform a stability analysis which permits us to identify the spectral properties of the intracavity field.
 S.Schütz and G. Morigi, Phys. Rev. Lett. 113, 203002 (2014)
 A. Campa, T. Dauxois, and S. Ruffo, Phys. Rep. 480, 57 (2009)