It is pointed out in this paper that so far G-L theory for the critical magnetic field of superconducting thin films has not been verified by experiments although G-L theory has been extensively used to describe the critical magnetic field of superconducting thin films in the past three decades and it is the only theory to describe the critical magnetic field of strong-eoupling superconducting thin films. We find that the critical magnetic field of weak-coupling superconducting crystalline thin films can't be described by G-L theory and that the critical magnetic field of strong-coupling superconducting thin films can't be adapted also.In this paper, we present a new local criterion, i.e.ξ≤λ,ξ≤d would be satisfied simultaneously in the thin film limit. By means of this new local Criterion, we can explain disagreement between theories and theory and experiments.
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