Regensburg 2002 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

TT: Tiefe Temperaturen

TT 11: Supraleitung: Elektronenstruktur, Phononen, Tunneln, Ordnungsparameter II

TT 11.1: Vortrag

Dienstag, 12. März 2002, 15:00–15:15, H19

Quasiclassical theory of ac Josephson effect in unconventional superconductors — •Andreas Poenicke¹, Juan Carlos Cuevas¹, and Mikael Fogelström² — ¹Institut für Theoretische Festkörkperphysik, Universität Karlsruhe, 76128 Karlsruhe, Germany — ²Institute of Theoretical Physics, Chalmers University of Technology and Göteborgs University, S-41296 Göteborg, Sweden

We present a theoretical description of the ac Josephson effect in unconventional superconducting junctions. Our approach is valid for arbitrary transparency of the junction and allows us to take into account the contribution of multiple Andreev reflections. In addition to the self-consistent determination of the order parameter, this formalism incorporates other crucial ingredients like bulk impurities, surface roughness and other pair-breaking mechanisms. We apply this theory to the case of the superconducting cuprates, in which it is believed that the order parameter has a dominant d-wave component. Our study throws light on three subjects presently under debate: (i) the possibility of observing the so-called subharmonic gap structure in d-wave junctions, (ii) the splitting of the zero energy bound states with magnetic field, and (iii) the possible existence of a subdominant order parameter.