Freie Weglängen im supraleitenden Zustand,im normalen Zustand und im Zwischenzustand

By size-effect measurements of the thermal conductivity of thin indium wires the mean free path of the excitations has been determined in the normal and in the superconducting state. Within the accuracy of these measurements, the mean free paths in the two states are found to be equal. — For the intermediate state the electron scattering from the interphase boundaries has been investigated both experimentally and theoretically. The experimental results can be explained with the aid of theBardeen-Cooper-Schrieffer theory of superconductivity.