Quantum phase transitions

  title={Quantum phase transitions},
  author={M. Lavagna},
  journal={Philosophical Magazine B},
  pages={1469 - 1483}
  • M. Lavagna
  • Published 7 February 2001
  • Physics
  • Philosophical Magazine B
Abstract We give a general introduction to quantum phase transitions in strongly correlated electron systems. These transitions, which occur at zero temperature when a non-thermal parameter g such as the pressure, chemical concentration or magnetic field is tuned to a critical value, are characterized by a dynamie exponent z related to the energy and length scales δ and ∂. We show how one can derive an effective bosonic model associated with fluctuations in the ordering fields. Simple arguments… 
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