Electrical characteristics of thin-film Ba/sub 2/YCu/sub 3/O/sub 7/ superconducting ring resonators

Author

Polakos, P.A. ; Rice, C.E. ; Schneider, M.V. ; Trambarulo, R.

Author_Institution

AT&T Bell Labs., Holmdel, NJ, USA

Volume

1

Issue

3

fYear

1991

fDate

3/1/1991 12:00:00 AM

Firstpage

54

Lastpage

56

Abstract

The microwave performance of superconducting microstrip ring resonators operating between 2 and 22 GHz is reported. The microstrip and ground plane for the resonators were fabricated from Ba/sub 2/YCu/sub 3/O/sub 7/ films deposited on both sides of the same LaAlO/sub 3/ substrate by coevaporation. Two ring resonator geometries differing in ring diameter were studied. The strip width was the same for both to maintain a fixed line impedance. The mean-ring diameters were 10.5 mm and 5.2 mm, giving fundamental resonance frequencies of approximately 2.4 GHz and 4.8 GHz, respectively. By patterning one side with a narrow ring, the resonators are produced with Q factors (at 9.5 GHz) in excess of 7500 at 75 K and 20000 at 25 K. The temperature dependence of the resonant frequency shows the behavior expected for a superconductor with an effective penetration depth of approximately 4500 AA. It is noted that the 75 K value represents an improvement of a factor of 20 over gold.<>

Keywords

barium compounds; high-temperature superconductors; resonators; strip line components; superconducting thin films; yttrium compounds; 10.5 mm; 2 to 22 GHz; 25 K; 4500 A; 5.2 mm; 75 K; Ba/sub 2/YCu/sub 3/O/sub 7/; LaAlO/sub 3/ substrate; Q factors; effective penetration depth; electrical characteristics; fundamental resonance frequencies; ground plane; high temperature superconductors; microwave performance; narrow ring; resonant frequency; ring diameter; ring resonator geometries; strip width; superconducting microstrip ring resonators; superconducting ring resonators; temperature dependence; Electric variables; Geometry; Microstrip resonators; Optical ring resonators; Resonant frequency; Substrates; Superconducting films; Superconducting microwave devices; Superconducting thin films; Transistors;

fLanguage

English

Journal_Title

Microwave and Guided Wave Letters, IEEE

Publisher

ieee

ISSN

1051-8207

Type

jour

DOI

10.1109/75.80721

Filename

80721