We theoretically study the nature of the flux lines in the cuprate oxide superconductors using a layer model in which superconductivity is primarily generated in the CuO2 layers by some electron pairing interaction and weak superconductivity is induced in other spacing layers by the proximity effect. In an external magnetic field parallel to the layers both the flux lines and their lattice are extremely anisotropic, and the flux lines are most stable in the weakly superconducting layers. Therefore, the layer structure itself works as an intrinsic pinning center. In the magnetic field perpendicular to the layers, the usual straight flux line is unstable, and the stable flux line is a spiral one propagating perpendicular to the layers. The amplitude and pitch of the spiral flux line depend on the anisotropy of superconductivity in the layered superconductors.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering