@article{2011-john, Abstract = {In this thesis, the interactions in an unbalanced Rubidium (Rb)-Caesium (Cs) mixture are studied, where the Cs atoms have been used as probes to study the interspecies interactions. The Rb atoms are trapped and stored in a conservative potential, in an optical dipole trap and cooled to quantum degeneracy. The coherent manipulation of the spin states is realized using a microwave and radio frequency radiation to prepare the Rb atoms in the various Zeeman split hyper ne levels of the ground state. Cs atoms are trapped in a MOT. An overlap of these two entities is obtained via a magnetic transport to study the interspecies interactions. The dynamics of the Cs MOT is studied in the presence of a 600nK thermal cloud of Rb, where a loss in the Cs atoms is observed. Rb remains una ected. Here, a method has been demonstrated, where the interspecies inelastic two- and three-body collisions have been investigated by monitoring the one- and two-atom loss rates in Cs. Each term in the complicated inelastic rate equation has been determined individually without having to solve the rate equation which can not be solved analytically. This is therefore, a nondestructive and simple method to extract information about the interactions and can be performed for future experiments with Cs in a conservative species speci c potential.}, Author = {John, S.}, Journal = {}, Pages = {}, Title = {{Towards Single Atom Aided Probing of an Ultracold Quantum Gas}}, Volume = {}, Year = {2011} }