Coherent atom optics

The experimental realisation of Bose-Einstein condensates in dilute alkali gases has opened up the possibility to perform time and space domain interferometry with coherent matter waves. We have exploited different configurations realising coherentmatter wave interferometers: in a first set of experiments we create a twofold condensate sample investigating the interplay between internal and external degrees of freedom in the matter wave analogous of a Young diffraction experiment. In a second experimental arrangement we produce a one dimensional array of condensates in an optical lattice. Upo n release from the optical lattice the condensates are made to interfere, the resulting interference pattern, this time analogous to an optical diffraction grating, is used to extract information about static and dynamical properties of the sample.