FINE-STRUCTURE OF THE SUPERCONDUCTING NORMAL AND NORMAL SUPERCONDUCTING TRANSITION

A non-linear fine structure of the superconducting-normal and normal-superconducting transition has been observed, based on the investigation of the temperature dependence of the ac susceptibility of high-T(c) superconductors. To detect this, a new research method, the so-called thermometric mapping, has been elaborated. Besides the usual intergrain and intragrain peaks, numerous springs on the dispersion and absorption curves have been shown, demonstrating the existence of the fine details of the gradual S-N or N-S transition. The model presented shows that the non-linearity is an inseparable property of quantum-mechanically coherent coupled systems.