Sensitive spectroscopy and atom dynamics in a single beam optical trap

Cold atoms are trapped in a dark optical trap which is created by a rapidly scanning far-detuned laser beams, where the scanning speeds is much faster than any characteristic atomic motional time scale. This concept offers the possibility to form nearly arbitrarily-shaped effective optical potentials and also to change them in real time. The spectroscopic and dynamical measurements in such a rotating beam trap are presented. The decay of ordered and chaotic systems by measuring lifetime of atoms in traps of different shapes which contains a small hole is experimentally investigated.