Search results

Sort By:

Limit search:

Bose-Einstein Condensates in Optical Lattices

100%

Wasilewski W., Trippenbach M., Rzążewski K.

Acta Physica Polonica A

2002

vol. 101

issue 1

47-60

We study an ultracold dilute gas of bosonic atoms in an optical lattice induced by intersecting laser beams. As a first approximation we neglect confining potential and atom-atom interactions. In this case the Gross-Pitaevskij equation reduces to simple Mathieu equation. Upon choosing periodic boundary conditions this problem has well known periodic solution. This simple picture allows to demonstrate localization of the wave packet and formation of the band structure. We calculate spectrum of the excited states as a function of the strength of modulating potential and using a standard adiabaticity criterion we predict the most efficient way to ramp up optical lattice, without higher state excitation. Finally, we discuss the influence of the atom-atom interaction (nonlinearity) on the adiabaticity of the process.

Nonlinear Effects with Ultrashort Laser Pulses

100%

Wasylczyk P., Wasilewski W., Trippenbach M., Radzewicz C.

Acta Physica Polonica A

2002

vol. 101

issue 1

89-104

Propagation of an intense femtosecond laser pulse through a transparent nonlinear medium such as dielectric leads to a number of phenomena. In our experiment we observed complex spatial, spectral, and temporal structures appearing in the initially smooth femtosecond laser pulse when the pulse power is comparable to or higher than the critical power for self-focusing. We have also developed a complete, 3-dimensional theoretical model to describe the observed phenomena.

Refine search results

2 Acta Physica Polonica A

2 2002

2 Trippenbach M.

2 Wasilewski W.

1 Radzewicz C.

1 Rzążewski K.

1 Wasylczyk P.

Search results

Bose-Einstein Condensates in Optical Lattices

Nonlinear Effects with Ultrashort Laser Pulses