title: Novel laser controlled variable matter wave beamsplitter.
abstract: We demonstrate a novel variable beam splitter using a tripod-linkage of atomic states, the physics of which is based on the laser control of the non-adiabatic coupling between two degenerate dark states. This coupling and the splitting ratio is determined by the time delay of the interaction induced by two of the laser beams.
authors.forename: H
authors.initials: H
authors.lastname: Theuer
authors.forename: R
authors.initials: R
authors.lastname: Unanyan
authors.forename: C
authors.initials: C
authors.lastname: Habscheid
authors.forename: K
authors.initials: K
authors.lastname: Klein
authors.forename: K
authors.initials: K
authors.lastname: Bergmann