A SWITCHABLE MICROWAVE DEVICE

摘要

A planar microwave device such as a transmission line comprises a patterned electrically conducting layer located on a dielectric layer (1) of uniform thickness. A central microstrip line (9) is enclosed by lateral (11) strips which are located on each side of the central strip and are connected to the central strip by bridge portions (15) to form windows (13). Each lateral strip has an interrupt region (17) located between the bridge regions. The interrupt regions can all be switched between an electrically conducting state and an electrically non-conducting or high resistance state. The state changes will affect the characteristic impedance of the transmission line in order to make it work e.g. in a transistor-like fashion or a switchable filter or inductor. The electrically conducting material can be a superconductor and the interrupt regions then contain Josephson junctions or superconducting weak links. Furthermore, the electrically conducting material can instead be a normal conductor and the interrupt regions can then comprise a photoconductive material.