Simultaneous optimization of the linear and nonlinear microwave response of YBCO films and devices

Citation
Jc. Booth et al., Simultaneous optimization of the linear and nonlinear microwave response of YBCO films and devices, IEEE APPL S, 9(2), 1999, pp. 4176-4180
Citations number
16
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
ISSN journal
10518223 → ACNP
Volume
9
Issue
2
Year of publication
1999
Part
3
Pages
4176 - 4180
Database
ISI
SICI code
1051-8223(199906)9:2<4176:SOOTLA>2.0.ZU;2-7
Abstract
We present results of a systematic study of the effect of film deposition t emperature on both the linear and nonlinear response of superconducting YBa 2Cu3O7-delta (YBCO) thin films and devices at microwave frequencies. Measur ements of the unpatterned films show that samples grown by pulsed laser dep osition at a lower substrate temperature (740 degrees C) display a smaller low-temperature residual surface resistance compared to films grown at a hi gher substrate temperature (780 degrees C). However, the same films which d isplay low residual surface resistance also show increased nonlinear effect s (measured by third harmonic generation) at all temperatures. Analysis of these results suggests that the increased defects present in the films grow n at the lower deposition temperature are responsible for both the lower su rface resistance and the higher third harmonic generation observed in these samples. We discuss the consequences of these results for the simultaneous optimization of both linear and nonlinear microwave properties of HTS thin films and devices.