title: Macroscopic quantum tunneling in d-wave YBa2Cu3O7-delta Josephson junctions.
abstract: The escape rate from the zero voltage state in a superconducting Josephson junction (JJ) is determined by the temperature, but it saturates at low temperature due to macroscopic quantum tunneling (MQT). Complications due to d-wave symmetry in a high temperature superconductor, like low energy quasiparticles and an unconventional current-phase relation, may influence the escape rate. We report, for the first time to our knowledge, the observation of MQT in a YBa(2)Cu(3)O(7-delta) grain boundary biepitaxial JJ. This proves that dissipation can be significantly reduced by a proper junction configuration, which is of significance for quantum coherence.
authors.affiliation: Quantum Device Physics Laboratory, Department of Microtechnology and Nanoscience, MC2, Chalmers University of Technology, S-412 96 Göteborg, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Bauch
authors.forename: F
authors.initials: F
authors.lastname: Lombardi
authors.forename: F
authors.initials: F
authors.lastname: Tafuri
authors.forename: A
authors.initials: A
authors.lastname: Barone
authors.forename: G
authors.initials: G
authors.lastname: Rotoli
authors.forename: P
authors.initials: P
authors.lastname: Delsing
authors.forename: T
authors.initials: T
authors.lastname: Claeson