DLRO, ODLRO and superfluidity

  • Yosuke Nagaoka
Excitonic Condensation
Part of the Lecture Notes in Physics book series (LNP, volume 57)


A necessary condition for superfluidity is discussed in connection with the classification of the long-range orders, DLRO and ODLRO, and it is concluded that it can take place only in systems with ODLRO. Based on this consideration, the possibility of superfluidity in a system of Frenkel excitons is examined. It is shown that it cannot occur in the excitonic phase, but that it can occur in the Bose-condensed phase of high-density excitons as a transient phenomenon.


Gauge Symmetry Spin System Anisotropy Energy Spontaneous Magnetization Transient Phenomenon 
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Copyright information

© Springer-Verlag 1976

Authors and Affiliations

  • Yosuke Nagaoka
    • 1
  1. 1.Department of PhysicsNagoya UniversityNagoyaJapan

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