Echoes in optical lattices

Summary form only given. The investigation of coherent superposition states for atoms interacting with external potentials allows a completely new class of experiments directed towards coherent trapping and guiding of neutral atoms. In addition, the process of decoherence, i.e. the collapse of superposition states, is one of the basic concepts for our understanding of the connection between classical and quantum physics. We study the creation and decay of superpositions of different components of the center-of-mass wavefunction of Rb atoms in a 1D near-resonant optical lattice.