S. Sakai et al., THEORY AND EXPERIMENT ON ELECTROMAGNETIC-WAVE-PROPAGATION VELOCITIES IN STACKED SUPERCONDUCTING TUNNEL STRUCTURES, Physical review. B, Condensed matter, 50(17), 1994, pp. 12905-12914
Characteristic velocities of the electromagnetic waves propagating in
vertically stacked Josephson transmission are theoretically discussed.
An equation for solving n velocities of the waves in an n Josephson-j
unction stack is derived. The solutions of two- and threefold stacks a
re especially focused on. Furthermore, under the assumption that all p
arameters of the layers are equal, analytic solutions for a generic N-
fold stack are presented. The velocities of the waves in two- and thre
e-junction stacks by Nb-Al-AlOx-Nb systems are experimentally obtained
by measuring the cavity resonance (Fiske step) modes. Comparison of t
he theory with the experimental data reveals good quantitative agreeme
nt.