Sudying Of Micriwave Coplanar Waveguide Resonatore In Low-Temperayure Superconducting State

With the development of low-temperature superconducting technology, coplanar waveguide (CPW) resonators have been widely used in lots of fields. For example, they have been used as quantum devices in, e.g. quantum computing, microwave parametric amplifiers, and the data bus for coupling the distant solid state qubits. As the probing devices, they have also been applied to detect the weak-light signals and cosmic rays.At present, the studied CPW resonators are divide into three types:one-half wavelength type, a quarter wavelength type, and the lumped compact type. One-half wavelength type has mainly utilized to implement the microwave parameter amplify and quantum information processing, while the latter two types are primarily applied to realize the weak-signal detections at high sensitivity. In this thesis the quarter-wavelength CPW resonators with high quality are investigated. We designed the resonators according to the relevant theoretical analysis and made the devices by magnetron sputtering, electron beam evaporation, and lithography. We measured the transmission characteristics of the devices by vector network analyzer (VNA) under an extremely-low temperature condition. The affects of the temperature or power on the transmission characteristics of the devices are discussed.The main work in the thesis may fall into four parts. Firstly, we briefly introduce the background of the topic, the research status and trends of the CPW resonators. Secondly, the working principle of the CPW resonators treating as the microwave kinetic inductance detectors (MIKDs) has been discussed by the Mattis-Bardeen and the two-level system theories, respectively. Accordingly, the fraction of internal inductance in total inductance is deduced. Thirdly, based on the RLC equivalent circuit we investigate transmission characteristic of the CPW resonators in the framework of the transmission line theory, microwave circuit and coplanar waveguide theory. The inferred expression of the phase shift across the CPW resonators are also studied. Nextly, we designed a half-wavelength and a quarter-wavelength CPW resonators by the software simulations and then fabricated the devices on high resistance silicon substrate by magnetron sputtering, electron beam evaporation, and lithography technologies. We measured the transmission characteristic of the devices, including the resonance frequency f0, the loaded quality factor QL, transmission parameter S21, the phase shift φ, and the resonance circle with Agilent E5071C vector network analyzer (VNA) at the100mK. The relevant results are:the resonance frequency f0=1.844505GHz and the loaded quality factor QL=4.4x105. Finally, the influences of the temperature and driving power on the propagation characteristic S21,phase shift φ of the resonators have been researched. The experimental results on the phase shifts for different temperatures or powers have been fitted numerically.