title: Vortex phase qubit: generating arbitrary, counterrotating, coherent superpositions in Bose-Einstein condensates via optical angular momentum beams.
abstract: We propose a scheme for the generation of arbitrary coherent superpositions of vortex states in Bose-Einstein condensates (BEC) using the orbital-angular-momentum states of light. We devise a scheme to generate coherent superpositions of two such counterrotating states of light using well-known experimental techniques. We show that a specially designed Raman scheme allows for transfer of the optical vortex-superposition state onto an initially nonrotating BEC. This creates an arbitrary and coherent superposition of a vortex and antivortex pair in the BEC. The ideas presented here could be extended to generate entangled vortex states, design memories for the orbital-angular-momentum states of light, and perform other quantum information tasks. Applications to inertial sensing are also discussed.
authors.affiliation: Quantum Computing Technologies Group, Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 126-347, Pasadena, California 91109-8099, USA. Kishor.T.Kapale@jpl.nasa.gov
authors.forename: Kishore T
authors.initials: KT
authors.lastname: Kapale
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Dowling