Doped Graphite May Be Superconductive Upto 230 C

[sanman]

Doped graphite has shown tantalizing hints of superconductivity at temperatures upto 230 Celsius:

http://www.nature.com/news/tantalizing-hints-of-room-temperature-superconductivity-1.11443

http://www.technologyreview.com/view/429203/room-temperature-superconductivity-found-in/

Heh - Graphite and Water - sounds like Steampunk

We could have had this 250 years ago, dammit - just think where we'd be now...

 

[sanman]

http://news.yahoo.com/warm-currents-graphite-powder-stirs-hints-room-temperature-222000449.html

 

[PhysTech]

This is not really a proof of room temperature superconductivity (RTS); it only shows "signs" of RTS. Further investigations are required to verify this claim. In the past, there have been many claims of room temperature superconductivity, which fell apart upon further investigation. In order to call something a superconductor it must demonstrate ALL of the following phenomenology:

(1) Zero resistance (in the dc limit)
(2) Meissner effect
(3) Persistent currents & fluxoid quantization
(4) Existence of magnetic critical fields
(5) Macroscopic phase coherence and quantum interference (due to Josephson pair tunneling effect)
(6) Gapped excitations

If even one of the above is not observed then it is not a superconductor. In the above study only the plots of magnetization versus temperature look "similar" to the ones obtained for cuprate high-temperature superconductors observed in the 1980s.

As the theorist Alexander Gurevich points out, this magnetic response could simply be the result of certain impurities. One can, however, make an argument at the other extreme: maybe if they improved the quality of the samples one may observe all of the above six effects. But that is just wishful thinking; but a possibility which cannot be ignored nevertheless.

To sum it all up, one can say that we have "signs" that could lead to a potential breakthrough. But at this moment we cannot say that we have "found it."