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A new method of measuring the dielectric constant and loss tangent of a dielectric thin film up to 5 GHz has been developed. The dielectric film has been deposited on a metal layer and capped with a top metal electrode layer. The capacitance is measured by using a vector network analyzer with a coplanar waveguide. Loss tangent as low as 0.001 can be measured with the use of the new technique.

A study was conducted on the radio frequency power dependence of large area YBCO thin films on LaAlO3 substrates. A coplanar waveguide resonator method was employed in determining the changes of inductance and loss vs circulating microwave currents. Correlations were observed between the radio frequency power dependence and penetration depth, crystal structures and other film properties.

Deals with a study which measured the basic interconnection performance of superconducting thin-film microstrip interconnection, with a sapphire dielectric and a superconducting ground plane. Transition temperature of superconducting microstrip transmission lines; Methodology of the study; Results and discussion.

Presents a study which measured the complex conductivity of thin superconducting niobium films using coherent time-domain terahertz spectroscopy. Experimental procedure; Results of the study; Conclusion.

Reports on the fabrication of YBa[sub2]Cu[sub3]O[sub7-δ]-normal metal-YBa[sub2]Cu[sub3]O[sub7-δ]step-edge Josephson junctions that fit the resistively shunted junction model with Johnson-Nyquist thermal noise. Expression for the ratio of the thermal energy to the supercurrent energy; Solution to the Smoluchowski equation.

In an effort to develop HTS superconducting filters with sufficient power handling capability for PCS (Personal Communication Services) base station transmit applications, we have undertaken a study of the power dependence of large area YBCO thin films on LaAlO/sub 3/ substrates. We employed a coplanar-wave-guide (CPW) resonator technique to obtain the changes of loss and inductance versus circulating microwave currents in the films. Data have been collected on uniform large area (2" diameter) films grown by coevaporation and off-axis sputtering techniques under varying deposition conditions. We found correlations between the RF power dependence and other film properties such as penetration depth and crystal structure. The most intrinsic sample, from the coevaporation technique, characterized by the smallest penetration depth, good orthorhombicity and absence of tetragonal phase, shows the least amount of nonlinearity. Such correlations can be used to prescreen films for fabrication and monitor the film production line. However, films from coevaporation and off-axis sputtering show very distinct power dependent behaviors. [ABSTRACT FROM PUBLISHER]

We study the propagation of terahertz bandwidth electrical pulses on high critical current density c-axis oriented YBa2Cu3O7-δ (YBCO) coplanar transmission lines deposited epitaxially on the low dielectric loss substrate lanthanum aluminate (LaAlO3). The losses on the YBCO transmission line are lower than on an equivalent gold line on the same substrate at temperatures below 50 K. At higher temperatures, absorption and dispersion of the ultrashort electrical pulses are observed in reasonable agreement with Mattis–Bardeen theory. [ABSTRACT FROM AUTHOR]

We report on a new process to make films of Y1Ba2Cu3O7 using coevaporation of Y, Cu, and BaF2 on SrTiO3 substrates. The films have high transition temperatures (up to 91 K for a full resistive transition), high critical current densities (106 A/cm2 at 81 K), and a reduced sensitivity to fabrication and environmental conditions. Because of the lower reactivity of the films, we have been able to pattern them in both the pre-annealed and post-annealed states using conventional positive photoresist technology. [ABSTRACT FROM AUTHOR]

Presents an electromagnetic model for planar stripe inductors based on thin metallic magnetic films. Application of magnetic films in high frequency planar magnetic flux devices; Structure of the electromagnetic model.