Penetration depth and critical current in NbN resonators: predicting nonlinearities and breakdown in microstrip

Author

Takken, T.E. ; Beasley, M.R. ; Pease, R.F.W.

Author_Institution

Edward L. Ginzton Lab., Stanford Univ., CA, USA

Volume

5

Issue

2

fYear

1995

fDate

6/1/1995 12:00:00 AM

Firstpage

1975

Lastpage

1978

Abstract

Parallel plate and microstrip resonator experiments show that NbN films have large magnetic penetration depth and a peak RF critical current density which either matches or exceeds the DC critical current density, depending on the temperature. The large penetration depth, /spl lambda/, suggests that narrow NbN transmission lines will have increased inductive nonlinearities, when compared with other superconductors. The relation between the DC and peak RF critical current densities indicates that by modeling the RF current distribution a simple DC breakdown measurement can be used to estimate a transmission line´s RF current carrying capacity.<>

Keywords

critical current density (superconductivity); microstrip resonators; niobium compounds; penetration depth (superconductivity); superconducting resonators; superconducting thin films; transmission lines; type II superconductors; DC breakdown measurement; NbN; NbN films; NbN resonators; RF current carrying capacity; RF current distribution; inductive nonlinearities; microstrip breakdown; microstrip resonator; narrow NbN transmission lines; parallel plate resonator; peak RF critical current density; penetration depth; type II superconductors; Critical current; Critical current density; Electric breakdown; Magnetic films; Microstrip resonators; Radio frequency; Superconducting films; Superconducting magnets; Superconducting transmission lines; Temperature dependence;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.402972

Filename

402972