Onset of dendritic flux avalanches in superconducting films.
We report a detailed comparison of experimental data and theoretical predictions for the dendritic flux instability, believed to be a generic behavior of type-II superconducting films. It is shown that a thermomagnetic model published very recently [Phys. Rev. B 73, 014512 (2006)10.1103/PhysRevB.73.014512] gives an excellent quantitative description of key features like the stability onset (first dendrite appearance) magnetic field, and how the onset field depends on both temperature and sample size. The measurements were made using magneto-optical imaging on a series of different strip-shaped samples of MgB2. Excellent agreement is also obtained by reanalyzing data previously published for Nb.
Denisov
D V
DV
Department of Physics and Center for Advanced Materials and Nanotechnology, University of Oslo, Post Office Box 1048 Blindern, 0316 Oslo, Norway.
Shantsev
D V
DV
Galperin
Y M
YM
Choi
Eun-Mi
EM
Lee
Hyun-Sook
HS
Lee
Sung-Ik
SI
Bobyl
A V
AV
Goa
P E
PE
Olsen
A A F
AA
Johansen
T H
TH