On the Importance of Time-Delay and the Use of Superconductors for Controlling it.

This paper discusses the importance of signal time-delay in high-speed and ultra high-speed electronic and opto-electronic circuits and systems. A very simple non-optical technique for controlling the time-delay of electronic signals in the sub-picosecond and femtosecond regime is proposed. The method relies on the temperature dependence of the penetration depth of a superconductor (the London penetration depth parameter lambda). Although applicable to conventional low-T sub c superconductors, the technique becomes more attractive and practical for the new high-T sub c superconductors due to the higher temperatures and much wider temperature range used.