Oscillating rows of vortices in superconductors.
Superconductors can be used as dissipation-free electrical conductors as long as vortices are pinned. Vortices in high-temperature superconductors, however, behave anomalously, reflecting the anisotropic layered structure, and can move readily, thus preventing their practical use. Specifically, in a magnetic field tilted toward the layer plane, a special vortex arrangement (chain-lattice state) is formed. Real-time observation of vortices using high-resolution Lorentz microscopy revealed that the images of chain vortices begin to disappear at a much lower temperature, Td, than the superconducting transition temperature, Tc. We attribute this image disappearance to the longitudinal oscillation of vortices along the chains.
Matsuda
T
T
Advanced Research Laboratory, Hitachi Ltd., Hatoyama, Saitama 350-0395, Japan.
Kamimura
O
O
Kasai
H
H
Harada
K
K
Yoshida
T
T
Akashi
T
T
Tonomura
A
A
Nakayama
Y
Y
Shimoyama
J
J
Kishio
K
K
Hanaguri
T
T
Kitazawa
K
K