Demonstration of a 20 GHz phase shifter using high-temperature superconducting SNS junctions

• Published in: IEEE transactions on applied superconductivity 1997-06, Vol.7 (2), p.3056-3059
• Main Authors: Berkowitz, S.J., Shih, C.F., Mallison, W.H., Zhang, D., Hirahara, A.S.
• Format: Article
• Language: English
• Subjects: Antenna feeds; Applied sciences; Circuit properties; Critical current; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; High temperature superconductors; Inductance; Josephson junctions; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Optical arrays; Performance loss; Phase shifters; Phased arrays; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Superconducting devices
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/77.621977

We have achieved a figure-of-merit of 90/spl deg//dB from a Co-doped Superconductor-Normal-Superconductor junction series array phase shifter, with 300 junctions The maximum observed phase shift was 25/spl deg/ from a 900 junction array. The entire device fits on a die size of 0.5/spl times/0.5 cm/sup 2/, which is suitable for integration into a phased array. However, the performance of this high-temperature superconductor device is still below the 150/spl deg//dB for a conventional shifter. In simulations, we see that an improved performance of 150-200/spl deg//dB is possible. If this performance can be achieved, the reduced base loss in addition to the reduction in loss from the antennas and feed lines in an integrated antenna array would lead to a system-wide performance advantage for a superconducting system.