Bose-Einstein Condensate dynamics with solitons

• Grant number: 12/23758-3
• Support type: Scholarships in Brazil - Master
• Effective date (Start): March 01, 2013
• Effective date (End): February 28, 2015
• Field of knowledge: Physical Sciences and Mathematics - Physics - Atomic and Molecular Physics
• Principal researcher: Vanderlei Salvador Bagnato
• Grantee: André de Freitas Smaira
• Home Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 98/14270-8 - Center for Optical and Photonics Science, AP.CEPID

Abstract

Bose-Einstein Condensates (BEC) are excellent macroscopic systems to observe the quantum behavior of matter. Since it experimental production in dilute atomic alkali gases trapped by magnetic fields, there are important aspects related to this system that have been intensely explored, like the collective modes of the harmonically trapped BEC, its tunneling through a potential barrier and the excited states of this system, that include the vortex and soliton. The latter consist of localized disturbances, which propagate without change of form. In this work, we investigate the singular aspects that coming from the dynamics of a composite system (trapped BEC containing a soliton). There are many studies that treat each part separately, that include a fundamental state BEC or a soliton inside a uniform infinite extent stationary BEC. We are basing on these previous analyses, besides mean-field numeric simulating our particular system submitted to diferent initial conditions (minimum harmonic potential trapped BEC or dislocated trapped BEC plus a soliton, in addition to a deformation in the potential) to characterize the tunneling dynamics. Some of our results could be explained using analytical predictions of the so called Thomas-Fermi approximation. At the end, we compar the meanfield simulations (Gross-Pitavskii equation) with the simulations from the multiple orbitals theory to justify the validity regime of our theory. (AU)