G. Wirth et al., Heavy ion induced columnar defects: a sensitive probe for the 2D/3D behaviour of vortex matter in high-temperature superconductors, NUCL INST B, 146(1-4), 1998, pp. 581-586
Heavy ion irradiation is used to create columnar defects in high-temperatur
e superconductors (HTS). The heavy ion induced defects are not only very we
ll controlled in shape and density, but also in the direction of the tracks
with respect to the crystallographic c-axis. Pinning of the flux lines as
a function of magnetic field orientation then becomes dependent on vortex d
imensionality. The two-dimensional (2D)/three-dimensional (3D) behaviour of
flux lines was investigated in the highly anisotropic Bi-based superconduc
ting oxide. Results obtained from transport current measurements with epita
xial films, measurements with small single crystals in flux transformer geo
metry and muon spin rotation (mu SR) data with relatively thick crystals ar
e compared. (C) 1998 Elsevier Science B.V. All rights reserved.