The use of a transmission line resonator offers the possibility for different sensor readout methods, e.g. flux qubit and kinetic inductance detectors. Both cases require a high quality factor, Q L , of the cavity circuit to detect small deviations in the resonance frequency.Various superconducting niobium coplanar waveguide resonators of λ/4 and λ/2 wavelength for 3 and 6 GHz were developed. Different layouts for the coplanar resonators were designed, simulated and measured on common silicon and sapphire substrates at 4.2 K. We found a very good agreement between simulation and measurement results, with Q L between 10 4 and 10 5 at helium temperatures. The presented results show the dependences on the chosen cross section geometries, the coupling factor and the complex layout of the transmission line.

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A device on a single 2"-LaAl03 wafer for a four bit instantaneous frequency measurement between 9.5 GEb and 10.5 GHz has been developed with coplanar YIBzC~O,I delay lines and power dividers. Compared to known triplate strip lines, coplanar delay lines are easier to fabricate monolithically and allow for a greater flexibility in the circuit design. Simulated and measured results are in good agreement.

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Superconducting transmission line resonators can be used to read out different sensors, e.g. flux qubit, transition edge sensor, or as detection element in kinetic inductance detectors. For both applications, high loaded quality factors of the microwave resonators are required, so that it is possible to detect small deviations in their resonance frequency. Thus high loaded quality factors lead to a high sensitive readout.Different coupling methods of quarter wavelength resonators in niobium thin-film technology are studied and optimized with respect to their maximum quality factor and usability for array building or multi-pixel design. Therefore different quarter wavelength resonator samples were designed, simulated, fabricated and measured on common silicon and sapphire substrates at liquid helium temperatures. We achieved an excellent agreement between the simulated and measured quality factors. The achieved values of the quality factor for the two-port resonators were in the range of 40,000 and for the one-port resonators up to = 1 000 000 at 4.2 K. The influence of the coupling coefficient on the quality factor was studied.