New metastable superconducting modification of bismuth attainable in ultrathin films

Journal Article · Tue Aug 01 04:00:00 EDT 1978 · Sov. J. Low Temp. Phys. (Engl. Transl.); (United States)

OSTI ID:6340831

Lazarev, B G; Semenenko, E E; Tutov, V I; Chupikov, A A

The superconductor properties of ultrathin (18--70 A) bismuth films were studied, these films having been produced by condensation of metal vapor on a surface cooled down to 2/sup 0/K. It has been established that the superconducting transition temperature becomes higher after annealing of such films and that the magnitude of this upward shift is a function of the film thickness. The maximum shift is ..delta..T/sub c/=0.9/sup 0/K for a film 18 A thick, the shift is smaller for films thicker than that, until there is no shift for films thicker than 40 A. The highest superconducting transition temperature after annealing of all specimens of all thicknesses did not exceed 3.6/sup 0/K. These data as well as the previously known anomalous dependence of dH/sub c//dT, electrical resistivity, and coordination structure of freshly condensed thin bismuth films on their thickness suggest that such films thinner than 40 A form as a different modification than that of thicker films. The hypothesis is proposed here that this modification is a distorted variant of the high-pressure Bi-II phase.

• Research Organization: Khar'kov Physicotechnical Institute, Academy of Sciences of the Ukrainian SSR
• OSTI ID: 6340831
• Journal Information: Sov. J. Low Temp. Phys. (Engl. Transl.); (United States), Journal Name: Sov. J. Low Temp. Phys. (Engl. Transl.); (United States) Vol. 4:8; ISSN SJLPD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ANNEALING
BISMUTH
CRITICAL FIELD
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
FILMS
HEAT TREATMENTS
MAGNETIC FIELDS
METALS
PHYSICAL PROPERTIES
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
ULTRALOW TEMPERATURE