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We study the creation of knotted ultracold matter waves in Bose-Einstein condensates via coherent two-photon Raman transitions with a $Lambda$ level configuration. The Raman transition allows an indirect transfer of atoms from the internal state $left| a rightrangle$ to the target state $left| b rightrangle$ via an excited state $left| e rightrangle$, that would be otherwise dipole-forbidden. This setup enables us to imprint three-dimensional knotted vortex lines embedded in the the probe field to the density in the target state. We elaborate on experimental feasibility as well as on subsequent dynamics of the matter wave.
We study the real-time dynamics of vortex lines in a large elongated Bose-Einstein condensate (BEC) of sodium atoms using a stroboscopic technique. Vortices are spontaneously produced via the Kibble-Zurek mechanism in a quench across the BEC transiti
Diffraction phenomena usually can be formulated in terms of a potential that induces the redistribution of a waves momentum. Using an atomic Bose-Einstein condensate coupled to the orbitals of a state-selective optical lattice, we investigate a hithe
We show that, in contrast to immediate intuition, Anderson localization of noninteracting particles induced by a disordered potential in free space can increase (i.e., the localization length can decrease) when the particle energy increases, for appr
We report on an extensive study of the elastic scattering time $tauS$ of matter-waves in optical disordered potentials. Using direct experimental measurements, numerical simulations and comparison with first-order Born approximation based on the know
We study the non-equilibrium dynamics of cold atoms held in an optical lattice potential. The expansion of an initially confined atom cloud occurs in two phases: an initial quadratic expansion followed by a ballistic behaviour at long times. Accounti