, Volume 22, Issue 5, pp 387–405 | Cite as

Phase transitions of a feedback amplifier

  • K Neelakantan
  • G Venkataraman
Statistical Physics


The phase transition behaviour of an amplifier with positive feedback is experimentally studied. The results are interpreted using catastrophe theory language. Zero (in Gilmore’s classification), first and second-order transitions are demonstrated by driving the system along appropriate trajectories in control parameter space and the cusp and the spinodal are mapped. The fluctuations of the order parameter are investigated and their relationship to system response time established. Quench experiments analogous to those familiar in condensed matter have also been performed and with similar results.


Nonequilibrium phase transitions catastrophe theory order parameter kinetics feedback amplifier 


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Copyright information

© the Indian Academy of Sciences 1984

Authors and Affiliations

  • K Neelakantan
    • 1
  • G Venkataraman
    • 1
  1. 1.Reactor Research CentreKalpakkamIndia

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