Nonlinear systems applied to atomic condensates with time-dependent interactions.

Author(s)

Hedhio Luiz Francisco da Luz

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Física (IF/SBI)
• Defense date: 2008-03-31

Examining board members

Lauro Tomio; Marcelo Martinelli; Marcelo Takeshi Yamashita

• Advisor: Lauro Tomio

Abstract

In this work the dynamics of a system of many particles in a ultra-low temperature regime was studied. We performed a dynamic study of two-dimensional condensate systems into a nonlinear optical lattice in one direction and also in the presence of an asymmetrical harmonic trap. We investigated some aspects of the stabilization and spread of solitons in a Bose-Einstein condensate. In the case of positive background field media (with attractive atomic systems), the collapse of the wave-packet is arrested by the dissipative periodic nonlinearity. The adiabatic variation of the background scattering length leads to metastable matter-wave solitons. When the atom feeding mechanism is used, a dissipative soliton can exist in an attractive bidimensional (2D) media with unidimensional (1D) periodic nonlinearity. In the case of repulsive condensates, with a negative background field, a stable soliton may exist when we have an harmonic trap in one direction and a nonlinear optical lattice in the other. Variational approach simulations are confirmed by full numerical results for the 2D Gross-Pitaevskii equation. (AU)

• FAPESP's process: 05/03209-1 - Nonlinear systems applied to atomic condensates with time-dependent interactions
• Grantee: Hedhio Luiz Francisco da Luz
• Support Opportunities: Scholarships in Brazil - Master