Superconductor metals

Tajima N, Sugawara N, Tamura M, Nishio Y, Kajita K (2006) Electronic phases in an organic conductor a-(BEDT-TTF)2l3 ultra narrow gap semiconductor, superconductor, metal, and charge-ordered insulator. J Phys Soc Jpn 75 051010/1-10... 

This study has been motivated by the recent discovery and investigations of a new family of superconductors metal-intercalated chloronitrides. For example, the compound Liu.48(THF)yHfNCl has arelatively high value of Tc 25K [l]-[5]. The mechanism of superconductivity for these materials had remained a puzzle. Indeed, according to theoretical calculations [6] the electron-phonon interaction is not sufficient to provide the observed value of Tc. Analysis of the data on heat capacity [2], based on the dependence 7 (1 + A), see [7], has led to a similar conclusion (7 is the Sommerfeld constant, A is the electron-phonon coupling constant). 

Superconductors (Metals, oxides, organic charge transfer salt)... 

Composite superconductor-metal materials Normal/superconducting... 

S. Sachdev, P. Werner, and M. Troyer (2004) Universal conductance of quantum wires near the superconductor-metal quantum transition. Phys. Rev. Lett. 92, p. 237003... 

Composite superconductor—metal material Normal / superconducting... 

Bardeen (along with Leon Neil Cooper and John Robert Schrieffer) won a second Nobel Prize in 1972 for their jointly developed theory of superconductivity, usually called (using the last initials of the three scientists) the BCS theory. In essence, BCS theory explains the phenomenon of superconductivity in Type I superconductors—metals, such as mercury, lead, and niobium. 

Gonductance of Nanowires near the Superconductor-Metal Quantum Transition. 

Manifestations of the proximity effect were observed as early as 1932 when it was noted that the contact resistance between a metal and a superconductor is reduced at the transition temperature of the superconductor [66J. However, significant data on the proximity effect were not collected until Meissner [67] evaluated the contact resistance behavior of over 63 superconductor/metal systems in 1960. Here it was noted that the contact resistance decreases at Tc in the case of many metal-superconductor junctions. Meissner accounted for the observed decrease in contact resistance by deeming it the result of a proximity effect. While the loss of contact... 

One of the most dramatic manifestations of the proximity effect is a supercurrent, or flow of current without resistance, which can be observed to occur over a mac-roscopically large distance through a normal conductor. The first set of experiments in which a supercurrent in a normal metal was directly observed were conducted in 1969 by Clarke [71]. A three-layered superconductor/ metal/superconductor sandwich was created in which copper was employed as the normal metal and lead was... 

Table 11.6. Temperature of superconductor metal transition for a few materials (with usual denomination in brackets)...

---