SPECTRAL-DOMAIN MODELLING OF SUPERCONDUCTING MICROSTRIP STRUCTURES

✍ Scribed by SMAIN AMARI; JENS BORNEMANN

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 267 KB
• Volume: 10
• Category: Article
• ISSN: 0894-3370
• DOI: 10.1002/(sici)1099-1204(199707)10:4<217::aid-jnm274>3.0.co;2-y

✦ Synopsis

We present an analysis of thin microstrip superconducting structures in which the effects of the superconducting material, of finite complex conductivity and finite thickness, are taken into account through the concept of sheet impedance coupled with an extension of the Spectral Domain Immittance Approach. The effect of the magnetic field on the penetration depth in the superconductor is included by solving the Ginzburg-Landau equations within the thin-film approximation (t/ 0 1). The state of the material is determined self-consistently in such a way that when the critical field is exceeded, the material systematically shifts from the superconducting to the normal state. Special attention is paid to the behaviour of the system in the neighbourhood of the critical temperature, T/T c Ӎ 1. We report that, in some cases, the propagation constant of a superconducting microstrip line attains a maximum when the real and imaginary parts of the conductivity are approximately equal. Numerical results for a microstrip line and a patch resonator are presented and compared with available data to document the validity of the approach.