Superconducting Polycrystalline Rhenium Films Deposited at Room Temperature.

We report on magnetron deposition of thin superconducting rhenium films on sapphire substrates. During the deposition, substrates were held at ambient temperature. Critical temperature of the films is T_c ~ 3.6 K. Films have polycrystalline structure, and grazing incidence X-ray diffractometry indicates that crystalline lattice parameters are somewhat larger compared to the bulk ones. Magnetoresistive and AC/DC susceptibilities allowed us to determine H_c1 and H_c2 of these films, as well as estimate coherence length ξ(0) and magnetic penetration depth λ_L(0). We also provide information on surface morphology of these films. [ABSTRACT FROM AUTHOR]