Dresden 2009 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 10: Superconductivity: Tunneling, Josephson Junctions, SQUIDs
TT 10.5: Talk
Monday, March 23, 2009, 15:15–15:30, HSZ 105
High frequency properties of Josephson π-junctions — •Georg Wild1,2, Christian Probst1, Achim Marx1, and Rudolf Gross1,2 — 1Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Walther-Meissner-Str. 8, 85748 Garching — 2Physik Department, Technische Universität München, Garching
Josephson junctions with ferromagnetic interlayer have attracted much interest
due to their potential application as π-phase shift elements. We have
developed a self-aligned multilayer process for the fabrication of
superconductor/insulator/ferromagnet/superconductor Josephson junctions (S=Nb,
I=AlOx, F=NiPd). Our junctions have RCSJ-like current-voltage
characteristics and a Fraunhofer diffraction pattern for the magnetic field
dependence of the critical current. The dependence of the IcRn-product on
the ferromagnet thickness shows a clear crossover from the zero- to the
π-state. We have determined the plasma frequency of π-coupled junctions
from Fiske resonances. This data is used to explain the different excitations
found in microwave spectroscopy experiments at milli-Kelvin temperature.
This work was supported by the DFG via SFB 631 and the Excellence Initiative via
NIM.