| Popis: |
Recent ultrasonic-attenuation studies have led to conflicting interpretations concerning the reduced anisotropy of the superconducting energy gap characteristic of impure Sn. Perz and Dobbs have concluded that the reduced anisotropy is only due to an averaging of the electron---sound-wave interaction over the Fermi surface, while we have concluded that under the specified conditions the reduced anisotropy is indeed a real measure of the superconducting properties. The two conclusions are discussed here in detail, and additional ultrasonic data are presented. Finally, comparison is made with recent thermal-conductivity measurements in impure Sn. |
