Title :
A superconducting microwave switch
Author :
Poulin, G.D. ; Hegmann, F.A. ; Lachapelle, J. ; Moffat, S.H. ; Preston, J.S.
Author_Institution :
Dept. of Eng. Phys., McMaster Univ., Hamilton, Ont., Canada
fDate :
6/1/1995 12:00:00 AM
Abstract :
We describe a superconducting microwave switch. The switch comprises a tapering microwave transmission line which can he switched from a very low loss ON state to a high impedance OFF state with a DC voltage applied to the transmission line through a bias-tee. Switching is essentially thermal in nature, occurring due to the formation of a ´hot spot´ in the transmission line. Thermal runaway is avoided through the use of voltage rather than current biasing. Once switched, the transmission line attenuates the applied microwave signal. An isolation of 20 dB is readily achievable. The intrinsic response time of the hot spot to applied microwave fields was estimated to be approximately 1 /spl mu/s by measuring the frequency dependence of the transmitted signal.<>
Keywords :
superconducting microwave devices; superconducting switches; 1 mus; DC voltage; bias-tee; hot spot; isolation; response time; superconducting microwave switch; tapering microwave transmission line; thermal runaway; thermal switching; Delay; Frequency estimation; Impedance; Propagation losses; Superconducting films; Superconducting microwave devices; Superconducting transmission lines; Switches; Transmission line measurements; Voltage;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
