We explain theoretically an oscillatory behaviour in space and time of the magnetic induction in Bi2Sr2CaCu2O8+δ crystals during magnetic relaxation. This new "flux waves" phenomenon appears near the order-disorder vortex phase transition, under specific conditions of temperature and induction gradient. Our theory is based on two coupled equations: The Landau-Ginzburg equation for the order parameter of the vortex phase transition and the diffusion equation for the magnetic induction. Linear stability analysis of these equations shows an appearance of oscillatory instabilities characterized by a period and wavelength that are in accordance with the experimental results.
Bibliographical noteFunding Information:
This research is supported by the Israel Science Foundation (ISF) – Centre of Excellence Program (Grant No. 8003/02) and the Heinrich Hertz Minerva Centre for High Temperature Superconductivity. Y.Y. and B.Ya.S. acknowledge support from the German–Israel Foundation (GIF). B.Ya.S. acknowledges a support from the ISF (Grant No. 4/03-11.7).
- Flux dynamics
- High temperature superconductors
- Vortex matter