Microwave properties of the system for TiO₂ sandwiched by Bi-based oxide superconductor

Abstract

We investigate the microwave properties and the superconducting behavior of the TiO₂ ceramics sandwiched by superconductor, BiSrCaCuO_7−x. The system presented the resonant frequency of 6.2 GHz, and the maximum relative permittivity was 40 although it depended on the thickness of TiO₂. Furthermore, thermal coefficients for any thickness of TiO₂ were very small such as 0.3 to 1.0 ppm/K, and the value (Q×f) relating to dielectric loss with the resonant frequency was a function which had the maximum value, 28000 GHz. We also studied the superconductivity of the system in which the TiO₂ did not much affect superconductivity. The system was regarded as a promising filter or oscillator material for satellite.

Key Words:

• Microwave
• TiO₂
• BiSrCaCuO_7−x superconductor
• resonant frequency
• dielectric resonator.