Unit:
Τομέας Ηλεκτρονικής Φυσικής και ΣυστημάτωνLibrary of the School of Science
Dissertation committee:
Δημήτριος Φραντζεσκάκης, Καθηγητής
Original Title:
Δυναμική, γένεση και διαχείριση σολιτονίων σε συμπυκνώματα Bose-Einstein
Translated title:
Dynamics, generation and manipulation of solitons in Bose-Einstein condensates
Summary:
The present thesis studies macroscopic nonlinear excited states of the
condensate, in the form of matter wave solitons. The different types of
solitons are studied in the framework of the mean- field theory and in
particular using the Gross-Pitaevskii (GP) equation in (1+1) dimensions. In
particular, the dynamics of the matter wave solitons are studied in
inhomogeneous atomic Bose- Einstein condensate mixtures (with space or time
dependance in the external potential and/or the scattering length), composed of
one or multiple different states of the same atomic species. Different
generation mechanisms of solitonic structures are suggested while the dynamics
and the stability of the respective solitons are achieved, by developing novel
perturbative analytical methods, based on the integrable limit of the
corresponding GP equations. Furthermore, it turns out that with appropriate
time or space modulation of the parameters of the equation (through the
scattering length, the frequency of the external potential, the Rabi coupling,
etc.) it is achievable to manipulate their dynamics. Numerical simulations are
also employed, and are found to be in a very good agreement with respect to the
analytical results.
Keywords:
Condensate, Soliton, Perturbation theory, Nonlinearity, Scattering length
Number of references:
182
