Annotation
A model is considered for the interaction of a single-mode boson field with a system of electrons placed at the nodes of an N-node lattice. Bogolyubov's approximating-Hamiltonian method is used to obtain an expression exact in the thermodynamic limit for the free-energy density in the system for the case of an arbitrary electron concentration ($0 < \bar{n} < 2$). The conditions for the existence of a superradiative state are derived.
© 2016 Publisher M.V.Lomonosov Moscow State University
Authors
A.V. Soldatov
Department of Theoretical Physics, Faculty of Physics, Moscow State University, Leninskie Gory, Moscow, 119992, Russia
Department of Theoretical Physics, Faculty of Physics, Moscow State University, Leninskie Gory, Moscow, 119992, Russia