Phase transition theory of many-mode ordering and pulse formation in lasers.

  title={Phase transition theory of many-mode ordering and pulse formation in lasers.},
  author={Ariel Gordon and Baruch Fischer},
  journal={Physical review letters},
  volume={89 10},
A novel theory for the ordering of many interacting modes in lasers is presented. By exactly solving a Fokker-Planck equation for the distribution of waveforms in the laser in steady state, equivalence of the system to a canonical ensemble is established, where the role of temperature is taken by amplifier noise. Passive mode locking is obtained as a phase transition of the first kind and threshold is calculated, employing mean field theory backed up by a numerical study. For zero noise… 

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