In-plane magnetic field dependence of intrinsic Josephson junctions in Tl-Ba-Ca-Cu-O thin films

Author

Warburton, P.A. ; Chana, O.S. ; Kuzhakhmetov, A.R. ; Hyland, D.M.C. ; Dew-Hughes, D. ; Grovenor, C.R.M. ; Koval, Y. ; Müller, P.

Author_Institution

Dept. of Electron. Eng., King´´s Coll., London, UK

Volume

11

Issue

1

fYear

2001

fDate

3/1/2001 12:00:00 AM

Firstpage

300

Lastpage

303

Abstract

We have fabricated intrinsic Josephson bridges using Tl-Ba-Ca-Cu-O thin films grown on vicinal lanthanum aluminate substrates. Measurements of the lock-in transition allow us align a magnetic field of up to 4 T with the copper oxide planes to better than 0.3°. This allows us to study the dynamics of Josephson fluxons in the films. For fields above 1.4 T and at low currents we observe Josephson flux creep. Above a field-dependent threshold current we observe free flow of the fluxons with a flux-flow resistance which is proportional to field. The fluxons reach a field-independent velocity before the jump to the quasiparticle branch occurs. Our results suggest that the development of a sub-mm-wave oscillator using these bridges will require sub-micron patterning

Keywords

Josephson effect; barium compounds; calcium compounds; flux creep; flux flow; high-temperature superconductors; quasiparticles; superconducting thin films; thallium compounds; 1.4 to 4 T; Tl-Ba-Ca-Cu-O; Tl-Ba-Ca-Cu-O thin film; flux creep; flux flow; fluxon dynamics; intrinsic Josephson junction; lanthanum aluminate substrate; lock-in transition; magnetic field; quasiparticle velocity; sub-MM-wave oscillator; superconducting bridge; threshold current; Bridges; Copper; Creep; Josephson junctions; Lanthanum; Magnetic field measurement; Magnetic fields; Magnetic films; Threshold current; Transistors;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.919343

Filename

919343