High-TC Superconducting Phase Shifters

An extensive study of problems related to the development of microwane digital phase shifters based on S-N transition of HTSC films under dc control current is performed. A new geometry for the HTSC switch with reduced inductivity is proposed. A design procedure and results of experimental investigation of 180-degrees phase shifters are presented. In the case of YBCO films on sapphire substrates no degradation effects in the S-N switches under dc and pulsed current were observed.