title: Doping-induced change in the interlayer transport mechanism of Bi_{2}Sr_{2}CaCu_{2}O_{8+delta} near the superconducting transition temperature.
abstract: We perform a detailed study of temperature, bias, and doping dependence of interlayer transport in the layered high temperature superconductor Bi_{2}Sr_{2}CaCu_{2}O_{8+delta}. We observe that the shape of interlayer characteristics in underdoped crystals exhibits a remarkable crossover at the superconducting transition temperature: from thermal activation-type above T_{c} to almost T-independent quantum tunneling-type below T_{c}. Our data provide insight into the nature of interlayer transport and indicate that its mechanism changes with doping: from the conventional single quasiparticle tunneling in overdoped to a progressively increasing Cooper pair contribution in underdoped crystals.
authors.affiliation: Department of Physics, Stockholm University, AlbaNova University Center, SE-10691 Stockholm, Sweden.
authors.forename: S O
authors.initials: SO
authors.lastname: Katterwe
authors.forename: A
authors.initials: A
authors.lastname: Rydh
authors.forename: V M
authors.initials: VM
authors.lastname: Krasnov