title: Experimental observation of high-order quantum accelerator modes.
abstract: Using a freely falling cloud of cold cesium atoms periodically kicked by pulses from a vertical standing wave of laser light, we present the first experimental observation of high-order quantum accelerator modes. This confirms the recent prediction by Fishman, Guarneri, and Rebuzzini [Phys. Rev. Lett. 89, 084101 (2002)]]. We also show how these accelerator modes can be identified with the stable regions of phase space in a classical-like chaotic system, despite their intrinsically quantum origin.
authors.affiliation: Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Schlunk
authors.forename: M B
authors.initials: MB
authors.lastname: D'Arcy
authors.forename: S A
authors.initials: SA
authors.lastname: Gardiner
authors.forename: G S
authors.initials: GS
authors.lastname: Summy