Andreev reflections at large ferromagnet/high-T_C superconductor area junctions with rough interface

Details Andreev reflections at large ferromagnet/high-T_C superconductor area junctions with rough interface Andreev reflections at large ferromagnet/high-T_C superconductor area junctions with rough interface

2007-12-13

arxiv.org/abs/0712.2131v2

Physics

Condensed Matter

Superconductivity

12 pages including 5 figures, title, text and figures have been revised

Scientific paper

Sub-gap conductance at a large area junction with a rough interface of a ferromagnet and a high-T$_{C}$ superconductor is superimposed by multiple peaks which is not expected from an ideal point contact Andreev reflection process. We demonstrate this phenomenon by measuring resistance as a function of bias voltage of a Co/Y$_{1}$Ba$_{2}$Cu$_{3}$O$_{7-\delta}$ junction with contact area 50 x 70 $\mu$ $m^{2}$ at various temperatures. In order to analyze such Andreev reflection data, the interface is assumed to have random potentials which can create local electric fields. The Blonder-Tinkham-Klapwijk theory is modified with the inclusion of a broadening parameter due to finite life time effects of quasi particles. An additional voltage drop due to local electric fields at the rough interface has been included in terms of an extra energy shift which may be related to the asymmetry of normalized resistance data. Spin polarization has been introduced for the ferromagnet. The presented model explains the multi-peak nature and asymmetry of Andreev reflection data experimentally observed at large area junctions. Extension of the model also interprets the experimentally observed anomalous enhancement of resistance peaks in the sub-gap region which may result from crossing the critical current limit across the junction.

Affiliated with

Also associated with

No associations

Rating

Andreev reflections at large ferromagnet/high-T_C superconductor area junctions with rough interface does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Andreev reflections at large ferromagnet/high-T_C superconductor area junctions with rough interface, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Andreev reflections at large ferromagnet/high-T_C superconductor area junctions with rough interface will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-622993