2008/05/27 by Alexey Novikov, Mikhail Ovchinnikov · 17 citations
Physics and Astronomy · #Anderson impurity model #Cold Atom Physics and Bose-Einstein Condensates #Degenerate energy levels #Diagrammatic reasoning #Dispersion relation #Impurity #Optical properties and cooling technologies in crystalline materials #Path integral formulation #Perturbation theory (quantum mechanics) #Quantum #Strong Light-Matter Interactions #Wave function #quant-ph
paper · pdf · doi:10.1088/1751-8113/42/13/135301
published in Journal of Physics A Mathematical and Theoretical 42(13), 135301 (Institute of Physics)
arxiv created 2008/05/27 · openalex publication_date 2009/03/04 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
In this paper we consider a quantum particle moving through dilute Bose–Einstein condensate at zero temperature. In our formulation the impurity particle interacts with the gas of uncoupled Bogoliubov's excitations. The perturbation theory for the Green's function of the impurity particle with respect to the impurity–condensate interaction is constructed by employing the coherent-state path integral approach. The perturbative expansion for the Green's function is resumed into the expansion for its self-energy part with the help of the diagrammatic technique developed in this work. The dispersion relation for the impurity clothed by condensate excitations is obtained and effective mass is evaluated beyond the Golden rule approximation.