An electron tunneling study of superconductivity in amorphous Sn{sub 1-x}Cu{sub x} thin films

Conference · Sat Apr 01 04:00:00 EST 1995

OSTI ID:135357

Naugle, D G; Watson, III, P W; Rathnayaka, K D.D.

The amorphous phase of Sn would have a superconducting transition temperature near 8 K, much higher than that of crystalline Sn with T{sub c} = 3.5 K. To obtain the amorphous phase, however, it is necessary to use a Sn alloy, usually Cu, and quench condense the alloy films onto a liquid He temperature substrate. Alloying with Cu reduces the superconducting transition temperature almost linearly with Cu concentration with an extrapolation of T{sub c} to zero for x = 0.85. Analysis of the tunneling characteristics between a normal metal electrode with an insulating barrier and superconducting amorphous Sn-Cu films provides detailed information on the changes in the electron-phonon coupling which determines T{sub c} in these alloys. The change from very strong electron-phonon coupling to weak-coupling with the increase in Cu content of amorphous Sn-Cu alloys for the range 0.08 is less than or equal to x is less than or equal to 0.41 is presented and discussed in terms of theories of electron-phonon coupling in disordered metals.

• Research Organization: National Aeronautics and Space Administration, Houston, TX (United States). Lyndon B. Johnson Space Center
• OSTI ID: 135357
• Report Number(s): N--96-10230; NASA-CP--3290-VOL-1; S--792-VOL-1; NAS--1.55:3290-VOL-1; CONF-940627--; CNN: NSF DMR-91-04194
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AMORPHOUS STATE
COPPER ALLOYS
ELECTRON-PHONON COUPLING
SUPERCONDUCTING FILMS
SUPERCONDUCTIVITY
THIN FILMS
TIN BASE ALLOYS
TRANSITION TEMPERATURE