--- res: bibo_abstract: - Steering a quantum harmonic oscillator state along cyclic trajectories leads to a path-dependent geometric phase. Here we describe its experimental observation in an electronic harmonic oscillator. We use a superconducting qubit as a nonlinear probe of the phase, which is otherwise unobservable due to the linearity of the oscillator. We show that the geometric phase is, for a variety of cyclic paths, proportional to the area enclosed in the quadrature plane. At the transition to the nonadiabatic regime, we study corrections to the phase and dephasing of the qubit caused by qubit-resonator entanglement. In particular, we identify parameters for which this dephasing mechanism is negligible even in the nonadiabatic regime. The demonstrated controllability makes our system a versatile tool to study geometric phases in open quantum systems and to investigate their potential for quantum information processing.@eng bibo_authorlist: - foaf_Person: foaf_givenName: M foaf_name: Pechal, M foaf_surname: Pechal - foaf_Person: foaf_givenName: Stefan foaf_name: Berger, Stefan T foaf_surname: Berger - foaf_Person: foaf_givenName: Abdufarrukh foaf_name: Abdumalikov, Abdufarrukh A foaf_surname: Abdumalikov - foaf_Person: foaf_givenName: Johannes M foaf_name: Johannes Fink foaf_surname: Fink foaf_workInfoHomepage: http://www.librecat.org/personId=4B591CBA-F248-11E8-B48F-1D18A9856A87 orcid: 0000-0001-8112-028X - foaf_Person: foaf_givenName: Jonas foaf_name: Mlynek, Jonas A foaf_surname: Mlynek - foaf_Person: foaf_givenName: L. foaf_name: Steffen, L. Kraig foaf_surname: Steffen - foaf_Person: foaf_givenName: Andreas foaf_name: Wallraff, Andreas foaf_surname: Wallraff - foaf_Person: foaf_givenName: Stefan foaf_name: Filipp, Stefan foaf_surname: Filipp bibo_doi: 10.1103/PhysRevLett.108.170401 bibo_issue: '17' bibo_volume: 108 dct_date: 2012^xs_gYear dct_publisher: American Physical Society@ dct_title: Geometric phase and nonadiabatic effects in an electronic harmonic oscillator@ ...