A new story in Science reports that an international team of researchers have been able to turn a non-superconducting form of copper oxide into a superconductor using a strong laser burst.
The team, working in Germany, Japan and the U.K., says it hopes its discovery might open a new path to high temperature superconductivity.
“We have used light to turn a normal insulator into a superconductor,” says Andrea Cavalleri, in a news release from Oxford University.
The group says it used a femtosecond pulses of a mid-infrared laser to transform non-superconducting (above 5 K) La1.675Eu0.2Sr0.125CuO4 (LESCO1/8) — a strip-ordered compound — into a transient superconductor. The material was at a base temperature under 20 K superconductor, and displayed superconductivity for a fraction of a second before returning to its normal state.
“We have shown that the non-superconducting state and the superconducting one are not that different in these materials, in that it takes only a millionth of a millionth of a second to make the electrons ‘synch up’ and superconduct,” says Cavalleri. “This must mean that they were essentially already synched in the non-superconductor, but something was preventing them from sliding around with zero resistance. The precisely tuned laser light removes the frustration, unlocking the superconductivity.”
Cavalleri, a professor in the Department of Physics at Oxford and the Max Planck Department for Structural Dynamics, Hamburg, continues. “That’s already exciting in terms of what it tells us about this class of materials. But the question now is can we take a material to a much higher temperature and make it a superconductor?”
Cavalleri’s group also included researchers from the Department of Advanced Materials Science, University of Tokyo, and the RIKEN Advanced Science Institute, Japan.