Title :
Doped-type coplanar junctions in the Bi/sub 2/Sr/sub 2/Ca/sub 1/Cu/sub 2/O/sub 8+/spl delta// system
Author :
Meltzow, A.C. ; Hu, S. ; Hollkott, J. ; Auge, J. ; Spangenberg, B. ; Kurz, H. ; Zakharov, N.D. ; Hesse, D.
Author_Institution :
Inst. fur Halbleitertech. II, Tech. Hochschule Aachen, Germany
fDate :
6/1/1997 12:00:00 AM
Abstract :
We report on a vertical Josephson junction in the Bi/sub 2/Sr/sub 2/Ca/sub 1/Cu/sub 2/O/sub 8+/spl delta// (BSCCO) system, based on a bilayer structure. A highly resistive bottom layer of Bi/sub 2/Sr/sub 2/(Ca/sub 1-z/Gd/sub z/)Cu/sub 2/O/sub 8+/spl delta// is deposited by DC-sputtering and covered by an undoped BSCCO layer with a T/sub c/ of typically 90 K. Junctions are formed by trenches patterned through the top layer into the resistive bottom layer. We found that the critical current I/sub c/ of the junctions is determined by the width of the grooves. Josephson coupling is demonstrated by Shapiro-like steps in the I-V curve up to a width of 0.8 /spl mu/m.
Keywords :
Josephson effect; bismuth compounds; calcium compounds; critical currents; high-temperature superconductors; sputter deposition; strontium compounds; superconducting junction devices; superconducting transition temperature; 0.8 mum; 90 K; Bi/sub 2/Sr/sub 2/(Ca/sub 1-z/Gd/sub z/)Cu/sub 2/O/sub 8+/spl delta//; Bi/sub 2/Sr/sub 2/Ca/sub 1/Cu/sub 2/O/sub 8+/spl delta// system; Bi/sub 2/Sr/sub 2/Ca/sub 1/Cu/sub 2/O/sub 8/; DC-sputtering; I-V curve; Josephson coupling; Shapiro-like steps; SrTiO/sub 3/; SrTiO/sub 3/ (100) substrate; bilayer structure; critical current; critical temperature; doped-type coplanar junctions; groove width; highly resistive bottom layer; microwave irradiation; trench patterning; vertical Josephson junction; Bismuth compounds; Degradation; Doping; Josephson junctions; Proximity effect; Resonant tunneling devices; Superconducting epitaxial layers; Surface resistance; Temperature dependence; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
