Atmosphere effects on Nb3Ge growth and superconductivity

Quantitative improvements are observed in the Tc, resistivity ratio, and reproducibility of superconducting Nb3Ge films coevaporated in air, N2, and O2 background pressures of 10−6–10−5 mm Hg. Tc onsets above 21.5 °K and (300 °K/25 °K) resistivity ratios above 2 are achieved. Pressures above the optimum result in degraded film properties.