Exact solution for a model of flux relaxation of high temperature superconductors

Some important recent experimental work on flux relaxation is in excellent agreement with a theoretical interpolation formula of elementary function with some parameters. In order to make the physical meaning of the quantities clear, an exact solution of the current relaxation law is obtained using the collective pinning and vortex glass models. This solution is of non-elementary function and is valid for the whole process. An analytical expression is obtained by the inversion method. The separation of the parameters is suggested. This solution method is also useful for other inversion problems, which occur in the physical experiments frequently.