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High dielectric constant enables Superconducting Meissner Transition at 77 degrees celsius or 170 degrees fahrenheit
Superconductors.ORG reports high Tc has been advanced to 77 Celsius (170F, 350K) with the discovery of the compound Tl7Sn2Ba2MnCu10O20+. This exceedingly high transition temperature (Tc) was achieved by substituting manganese into the titanium atomic sites of the 65 Celsius superconductor announced in January 2014. This substitution increases the dielectric constant (K) of the anion in the “light” region of the H212 structure by two orders of magnitude.
Two examples of the Meissner transitions which consistently appeared near 77C in more than a dozen magnetization tests2. This is the 17th material found to display superconductivity above room temperature.
The graph below shows how Tc increases in the H212 structure as the dielectric constant (K) increases exponentially. As dioxides, silicon has a K of only 4, while titanium is near 100 and manganese has a colossal K near 10,000. The rise in Tc occurs despite the planar-weight-ratio (PWR) declining with progressively heavier elements (see right side of graph). Normally Tc goes down as PWR goes down.
Source: http://nextbigfuture.com/2014/02/high-dielectric-constant-enables.html
