5 papers · 1 filter
Phase diagram of geometric d-wave superconductor Josephson junctions
A. Gumann, N. Schopohl
We show that a constriction-type Josephson junction realized by an epitactic thin film of a d-wave superconductor with an appropriate boundary geometry exhibits intrinsic phase dif…
Geometric pi Josephson junction in d-wave superconducting thin films
A. Gumann, C. Iniotakis, N. Schopohl
A novel way to realize a pi Josephson junction is proposed, based on a weak link in an unconventional d-wave superconductor with appropriately chosen boundary geometry. The critica…
Microscopic Theory of Superconductor-Constriction-Superconductor Josephson Junctions in a Magnetic Field
A. Gumann, T. Dahm, N. Schopohl
Self-consistent solutions of microscopic Eilenberger theory are presented for a two-dimensional model of a superconducting channel with a geometric constriction. Magnetic fields, e…
Vortex core shrinkage in a two gap superconductor: application to MgB2
S. Graser, A. Gumann, T. Dahm +1
As a model for the vortex core in MgB2 we study a two band model with a clean sigma band and a dirty pi band. We present calculations of the vortex core size in both bands as a fun…
Induced Kramer-Pesch-Effect in a Two Gap Superconductor: Application to MgB2
A. Gumann, S. Graser, T. Dahm +1
The size of the vortex core in a clean superconductor is strongly temperature dependent and shrinks with decreasing temperature, decreasing to zero for T -> 0. We study this so-cal…