title: Berry phase in a composite system.
abstract: The Berry phase in a composite system with one driven subsystem has been studied in this Letter. We choose two coupled spin-1 / 2 systems as the composite system; one of the subsystems is driven by a time-dependent magnetic field. We show how the Berry phases depend on the coupling between the two subsystems, and the relation between the Berry phases of the composite system and those of its subsystems.
authors.affiliation: Department of physics, Dalian University of Technology, Dalian 116024, China.
authors.forename: X X
authors.initials: XX
authors.lastname: Yi
authors.forename: L C
authors.initials: LC
authors.lastname: Wang
authors.forename: T Y
authors.initials: TY
authors.lastname: Zheng