Planar SFS Josephson Junctions Made by Focused Ion Beam Etching
Abstract
Superconductor-Ferromagnet-Superconductor (S-F-S) Josephson junctions were fabricated by making a narrow cut through a S-F double layer using direct writing by Focused Ion Beam (FIB). Due to a high resolution (spot size smaller than 10 nm) of FIB, junctions with a small separation between superconducting electrodes ( 30 nm) can be made. Such a short distance is sufficient for achieving a considerable proximity coupling through a diluted CuNi ferromagnet. We have successfully fabricated and studied S-F-S (Nb-CuNi-Nb) and S-S'-S (Nb-Nb/CuNi-Nb) junctions. Junctions exhibit clear Fraunhofer modulation of the critical current as a function of magnetic field, indicating good uniformity of the cut. By changing the depth of the cut, junctions with the product ranging from 0.5 mV to V were fabricated.
Cite
@article{arxiv.cond-mat/0411152,
title = {Planar SFS Josephson Junctions Made by Focused Ion Beam Etching},
author = {V. M. Krasnov and O. Ericsson and S. Intiso and P. Delsing and V. A. Oboznov and A. S. Prokofiev and V. V. Ryazanov},
journal= {arXiv preprint arXiv:cond-mat/0411152},
year = {2009}
}
Comments
5 pages, 5 figures, presentation at EUCAS-2003, to be published in Physica C