High-Tc Superconducting Microwave and Millimeter Devices and Circuits—An Overview

Abstract

High temperature (high-Tc) superconductors (HTS) have found many applications in the last two decades. To microwave researchers and engineers, the ultra-low surface resistance of the thin-film HTS materials at microwave and millimeter frequencies and the highly non-linear Josephson junctions are of particular interest. The former can be exploited in the design and fabrication of passive microwave components and circuits with superior performance, and the latter can be exploited to create many novel active HTS devices. This paper provides an overview of the state-of-art development of HTS devices and circuits for microwave and mm-wave communication front-end receiver systems. The paper is particularly focused on the latest advancement of HTS Josephson junction based active devices, monolithic microwave integrated circuits (MMIC), and whole receiver systems integrated with cryocoolers.INDEX TERMS Filters, high temperature superconductors (HTS), Josephson junction, mixers, receivers.

Superconducting Notch Filter for RFI Mitigation in Ground-Based Radio Telescope

“…The self-coupled hairpin resonator geometry provides the necessary shunt reactance to achieve higher stop-band rejection, demonstrates good quality factors to avoid significantly increasing insertion loss in the observation bands, and avoids the use of narrow-width microstrip or interdigital features. Current concentration at the resonator edges are the limiting factor in power handling capacity of HTS filters [5]. Using small features as in some other designs [6], [7] increases the amount of fringing electric fields along the microstrip edges and risks degrading the filter's performance while exposed to the local, high-power RFI source.…”