Graduate School in Nonlinear Science

Sponsored by the Danish Research Academy

Underdamped long Josephson junction coupled to overdamped single-flux-quantum circuits-experiment and simulation

by Yongming Zhang
Conductus, Inc.
Sunnyvale, CA 94086
U.S.A.

Thursday, June 18, 1998 13:00 h
at MIDIT, Building 305 room 027

MIDIT-seminar No. 407

Abstract:We report a novel circuit that integrates an underdamped long Josephson junction with overdamped single-flux-quantum (SFQ) circuits. Our experiments confirm that the resonant soliton models in the long junction are not affected by SFQ cells coupled to the junction, and demonstrate that the radiation frequency and linewidth of the soliton resonances can be measured with SFQ T-flip-flop. A numerical model for investigating a long junction coupled to shunted JTL cells is also developed. Our measurement and numerical simulation also show, for the first time, that a 4

quantum mechanical phase leap at the end of the long junction, which is due to the reflection of a soliton, create two single flux quantum propagating in the overdamped Josephson transmission line.