Experimental study of the quantum driven pendulum and its classical analogin atom optics - art. no. 033407

We present experimental results for the dynamics of cold atoms in a far det uned amplitude-modulated optical standing wave. Phase-space resonances cons titute distinct peaks in the atomic momentum distribution containing up to 65% of all atoms resulting from a mixed quantum chaotic phase space. We cha racterize the atomic behavior in classical and quantum regimes and we prese nt the applicable quantum and classical theory, which we have developed and refined. We show experimental proof that the size and the position of the resonances in phase space can be controlled by varying several parameters, such as the modulation frequency, the scaled well depth, the modulation amp litude, and the scaled Planck's constant of the system. We have found a sur prising stability against amplitude noise. We present methods to accurately control the momentum of an ensemble of atoms using these phase-space reson ances which could be used for efficient phase-space state preparation.