Superconducting transition temperature of cold-deposited indium films
Аннотация
The temperature dependence of the superconducting transition temperature Tc has been investigated for thin indium films (200–18 Å), obtained by condensing the metal vapor in a vacuum better than 10−10 mm Hg onto a glass substrate cooled down to 2 K. As the thickness is decreased from 200 to 18 Å, Tc increases from 4.20 to 4.65 K. The resistivity at the same time increases from 4 to 180μΩ·cm. The behavior of Tc(d) is explained by the further softening of the phonon spectrum of cold-deposited indium films on reducing their thickness with a simultaneous increase in the electron–phonon coupling constant.