Reduction Of The Capacitance Of Niobium Based Josephson Junctions
Original Publication Date: 1979-Oct-01
Included in the Prior Art Database: 2005-Feb-20
The high dielectric constant ( Epsilon (1) approximately N 30) of (2) O(5) results in a high capacitance of Nb-based junctions in which the barrier is formed by the native oxide. This, in turn, creates difficulties in some circuits, necessitating either alternative designs and/or resulting in an increase in switching time. Use of foreign barrier materials, having a low dielectric constant, have been mainly unsuccessful due to difficulties in obtaining perfect coverage and thickness uniformity consistent with adequate control of the Josephson current density.