Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

TT: Tiefe Temperaturen

TT 7: Superconductivity & Solids At Low Temperature - Poster Session

TT 7.50: Poster

Montag, 27. März 2006, 14:00–17:45, P1

Current and phase distribution in Josephson junctions with ferromagnetic interlayer — •Martin Weides¹, Dietmar Doenitz², Hermann Kohlstedt^1,3, Dieter Koelle², and Reinhold Kleiner² — ¹Institute for Solid State Research, Research Centre Juelich, Germany — ²Physikalisches Institut - Experimentalphysik II, Universität Tübingen — ³Department of Material Science and Department of Physics, University of Berkeley, USA

We use Low Temperature Scanning Electron Microscopy (LTSEM) to image current and phase distribution in low-T_C SINFS Josephson junctions (JJ) with diluted ferromagnetic Ni₆₀Cu₄₀ used as F-interlayer. Our technology [1] enables us to fabricate high quality junctions with low parameter spread. The configuration of magnetic domains in the F-interlayer is, amongst others, determined by the shape-anisotropy. The in-plane magnetization forms magnetic domains, which influence Cooper pair and quasiparticle transport trough the F-interlayer. We use annular and elliptical junction geometries for this work.
The imaging is based on the electron-beam-induced local heating of a resistively biased junction [2]. The beam-induced voltage-change is detected by Lock-In technique and is proportional to the Josephson current. The interaction between the local magnetic configuration of the JJ and external magnetic fields with respect to the transport current is studied.
[1] Weides et al., to appear in Physica C
[2] R. Gross and D. Koelle, Reports on Progress in Physics 57 (1994)