SCL member Ivana VIdanovic held a seminar talk entitled "Nonlinear BEC Dynamics Induced by Harmonic Modulation of Atomic s-wave Scattering Length".

Abstract of the talk:

In the recent experiment whose results are published in Phys. Rev. A 81, 053627 (2010), a Bose-Einstein condensate of ⁷Li has been excited by a harmonic modulation of the atomic s-wave scattering length via Feshbach resonance. Combining an analytical perturbative approach with numerical simulations we analyze the resulting nonlinear dynamics of the system on the mean-field Gross-Pitaevskii level. Our detailed results show the presence of higher harmonics and mode coupling. Most importantly, we also find significant shifts of the collective modes frequencies in the resonance region which are due to the nonlinearity of the system dynamics. Finally, we indicate how these frequency shifts could be measured in a future experiment.