Superconducting beryllium films deposited by ion-beam-sputtering

Abstract

The properties of beryllium thin films deposited by ion-beam-sputtering (IBS-Be) are investigated, IBS-Be films with high superconducting transition temperatures (T <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</inf> 'S = 6-7 K) have an amorphous-like structure. T <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</inf> 's show thermal stabitlity up to 480 K. IBS-Be/BeO/Pb junctions with low leakage conductance indicate IBS-Be base electrodes do not deteriorate and that the Be-oxidized layers function as good tunnel barriers, The deduced value of the electron density of states at the Fermi level remains as low as that for bulk beryllium. IBS-Be films are considered to be advantageous for applications to tunneling and Abrikosov vortex devices.