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Phase transition in a model two-level system

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A two-level Bose-system interacting with a multimode Fermi-field is considered. The path integration method is used to obtain the spectrum of the collective excitations below the phase transition point in the superradiant state. The question of phase transition stability is investigated.

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Literature cited

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    Y. K. Wang and F. T. Hioe, “Phase transition in the Dicke model of superradiance,” Phys. Rev. A,7, No. 3, 831–836 (1973).

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    A. F. Sadreev, “Collective radiative phenomena in two-level systems,” Zh. Eksp. Teor. Fiz.,77, No. 3, 829–842 (1979).

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Additional information

Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 101, pp. 184–195, 1981.

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Fedotov, S.A. Phase transition in a model two-level system. J Math Sci 23, 2487–2494 (1983). https://doi.org/10.1007/BF01084177

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  • Phase Transition
  • Integration Method
  • Transition Point
  • Path Integration
  • Transition Stability