Luca Leuzzi — NANOTEC-CNR Roma #
The glassy random laser: replica symmetry breaking in the intensity fluctuations of laser emission spectra #
The behavior of a recently introduced overlap parameter is
  analyzed, measuring the correlation between intensity
  fluctuations of waves in random media in different physical regimes,
  with varying amount of disorder and non-linearity.  Its relationship
  is established to the standard Parisi overlap order parameter in the
  replica theory for spin-glasses.  In the recently introduced complex spherical
  spin-glass model, describing the onset and behavior of random
  lasers, replica symmetry breaking in the intensity fluctuation
  overlap is shown to occur at high pumping or low temperature. 
  This order parameter identifies the laser transition in random media
  and describes its glassy nature in terms of emission spectra data,
  the only data so far accessible in random laser measurements.
  The theoretical analysis is, eventually, compared to recent spectroscopy
  measurements demonstrating the validity of the theory and providing a
  straightforward interpretation of different spectral behaviors in
  different kinds of random lasers.