Microwave and Millimeter-Wave Low-Temperature Superconductor Devices

Superconductor-based microwave and millimeter-wave components play a crucial role in various applications, particularly in superconductor-based digital receivers and superconductor-based quantum computing systems. This article aims to provide an overview of recent advancements in superconductor microwave and millimeter-wave devices implemented in a multilayer nio­bium fabrication process. These devices cover a broad frequency range, from 300 MHz to 100 GHz, and include bandpass/band-reject filters, wideband cou­plers, niobium-based microelectromechanical sys­tems switches, phase shifters, filters-based power protection circuits, phase shifter-based power limiters, tunable attenuators, and supercon­ductor-based magnet-less circulators.