Up until recently, all superconducting materials required a significant amount of chemical tinkering and a temperature no higher than -140 degrees Celsius.
Needless to say, such feats of ingenuity are quite pricy and highly impractical when it comes to real-world applications.
Eliminating the need for expensive cooling could revolutionize energy transmission, medical scanners and transport.
Recently, a group of physicists reported achieving just that – by arranging two layers of graphene such that a pattern is formed where carbon atoms are offset by an angle of 1.1° the team had achieved superconductivity at a much higher temperature than ever before.
Two studies published in the journal Nature to detail the discovery also claim that superconductivity of graphene is of the unconventional type, meaning it cannot be explained by the mainstream theory of superconductivity.
Researchers had predicted the so-called “magical angle” would cause the atoms to interact in various interesting ways when sandwiched between layers of 2D materials, but no one was really expecting it to lead to superconductivity.
The exact manner in which electrons interact in unconventional superconductors remains a source of disagreement in the physics community to this day – forces that “glue” electrons into pairs remain a prominent bottleneck in the field of high-temperature superconductivity.
With the advent of graphene superconductors, however, this might soon change. Studying graphene-based devices will be much simpler compared to cuprates, as all that’s required is a simple tweak in the electric field.
While it’s still too early to say whether all the fascinating behaviours seen in cuprates is really taking place in the new-and-improved graphene, the significance of the new discovery is already widely recognised.
According to the physicist and Nobel laureate Robert Laughlin from Stanford University in California, physicists have been stumbling around the dark for 30 years trying to understand cuprates. “Many of us think that a light just switched on”.