DLRO, ODLRO and superfluidity
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.
KeywordsGauge Symmetry Spin System Anisotropy Energy Spontaneous Magnetization Transient Phenomenon
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