Proceedings of the Steklov Institute of Mathematics
Rigorous results of phase transition theory in lattice boson models
Дмитрий Петрович Санкович
Abstract
Quantum systems of particles obeying Bose statistics and moving in d -dimensional lattices are studied. The original Bose–Hubbard Hamiltonian is considered, together with model systems related to this Hamiltonian: the Bose–Hubbard model with exchange interaction of infinite radius and the Bose–Hubbard model with infinite interaction potential. Rigorous results concerning the proof of the existence of Bose condensation and a phase transition to the Mott insulator state in these systems are presented.