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CENTER FOR APPLIED MATHEMATICS AND THEORETICAL PHYSICS
UNIVERZA V MARIBORU UNIVERSITY OF MARIBOR
KREKOVA 2 SI-2000 MARIBOR SLOVENIA
Phone +(386) (2) 2355 350 and 2355 351 $\bullet$ Fax +(386) (2) 2355 360
Robnik@uni-mb.si $\bullet$ www.camtp.uni-mb.si
PROF.DR. MARKO ROBNIK, DIRECTOR

Seminarsko predavanje
Centra za uporabno matematiko in teoreticno fiziko

Formation and Complex Dynamics of BEC Bright Solitons

Dr. Luca Salasnich
Instituto Nazionale per la Fisica della Materia, Milano, Italy
Dipartimento di Fisica, Universita di Milano

Abstract: We discuss the formation of bright solitons in a Bose-Einstein condensate (BEC) of 7Li atoms induced by a sudden change in the sign of the scattering length from positive to negative, as reported in a recent experiment [1]. The numerical simulations are performed by using the Gross-Pitaevskii equation (GPE) with a dissipative three-body term. We show that a number of bright solitons is produced and this can be interpreted in terms of the modulational instability of the time-dependent macroscopic wave function of the BEC. In particular, we derive a simple formula for the number of solitons that is in good agreement with the numerical results. By investigating the long time evolution of the soliton train we find that adjacent solitons repel each other due to their phase difference. In addition, we find that during the motion of the soliton train in an axial harmonic potential the number of solitonic peaks changes in time and the density of individual peaks shows an intermittent behavior [2].
References
$[1]$ K.E. Strecker et al., Nature 417, 150 (2002). $[2]$ L. Salasnich, A. Parola, and L. Reatto, Phys. Rev. Lett. 91, 080405 (2003).

Seminarsko predavanje bo v petek 24. oktobra 2003 ob 15:15 uri v seminarski sobi CAMTP, Krekova 2, pritlicje. Vljudno vabljeni vsi zainteresirani, tudi študenti.

Prof.Dr. Marko Robnik
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