QUANTUM BREATHERS IN AN ATTRACTIVE FERMIONIC HUBBARD MODEL Quantum breathers in a Hubbard model
نویسنده
چکیده
In one–dimensional translationally invariant anharmonic lattices, an extended Bloch state with two or more strongly correlated particles is usually called a quantum breather. Here we study an attractive fermionic Hubbard model with two kind of particles of opposite spin. We discuss the existence of breathers, and several effects that break the translational symmetry of the system and localize the breather in the lattice.
منابع مشابه
Linköping Studies in Science and Technology, Dissertation No. 1775
This thesis is mainly concerned with theoretical studies of two types of models: quantum mechanical Bose-Hubbard models and (semi-)classical discrete nonlinear Schrödinger (DNLS) models. Bose-Hubbard models have in the last few decades been widely used to describe Bose-Einstein condensates placed in periodic optical potentials, a hot research topic with promising future applications within quan...
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تاریخ انتشار 2003