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Scientists from Canada and Europe have published results showing that “decoration” of graphene samples with lithium can change the behavior of electrons passing through it and turn the super-material into a superconductor. It’s a property that was first predicted by a super-computer, now confirmed through physical experiment. It’s a breakthrough that could herald a new age of graphene electronics — though it’s still got a long way to go.

Graphene is often referred to as having very low electrical resistance — and it does — but the reality is that when compared with a true superconductor, a shielded wire made of graphene may as well be a block of wood. Superconductors are finicky, technical creations that depend on just one property for their definition: 100% of any electricity put into a superconducting system at one end must come out the other, unhindered by resistance of any kind.

In 2012, researchers used computer models to predict that graphene could enter a superconducting state if it were studded with lithium atoms. These atoms would change the overall distribution of electrons in the whole, donating an oddity of electron distribution called a phonon (not a photon!) to the molecule of graphene. These phonons are thought to bind flowing electrons together into so-called Cooper Pairs, which move together through a superconductor without any energy lost to resistance.

A diagram of the internal workings of the superconducting grid power cable in Essen, Germany.

There are still very low temperatures involved here. The “decoration” process in which the lithium atoms are attached takes place at just 8K, or -265.15 °C. Their measured transition temperature for superconducting graphene was even lower: 5.9K, or -267.25 °C.

That means that while graphene has been induced to have a truly incredible electrical property, it has not solved all our earthly technological problems. The big problem with the superconductors scientists have managed to create is that they all, like graphene, require cooling to “cryogenic” temperatures to work, meaning that we can’t create large or inexpensive quantities of superconductors for things like large-scale grid power upgrades or cheap fusion containment rigs.

However, some scientists believe that carbon, and in particular carbon in the form of graphene, has good prospects for development into a (relatively) high-temperature superconductor. The issue will be further modifying the movement of electrons, so they can move resistance-free through ever more energetic (hot) atomic crystal lattices.

A graphene-based CMOS chip from IBM.

One interesting facet of this research is the fact that, as mentioned, the superconducting property was predicted by a computer model of graphene electronics. Being so simple and highly ordered, graphene presents a nice and relatively simple arena for physicists to test their understanding of these issues. If graphene tests like this one can refine atomic simulations, those simulations might be able to predict even more complex or unlikely molecules with even more impressive characteristics.

Of course, the virtue of graphene is not so much that it can be made into long wires like electrical table, but into small ones like computer transistors. A superconducting graphene processor wouldn’t just pack transistors far more tightly than silicon, but it would produce very little heat while doing so, allowing increases in die size and density. Like most possible breakthroughs in superconductors, this one has the potential to change the world — but it’s still got to get over some of the same basic hurdles as other, more mundane, superconducting materials.