US physicists create thinnest superconducting metal
A superconducting metal sheet with just two atoms thick has been developed by physicists at the University of Texas in Austin.tech reviews Updated: Jun 09, 2009 10:40 IST
A superconducting metal sheet with just two atoms thick has been developed by physicists at the University of Texas in Austin.
The university said in a statement Monday that it was the thinnest superconducting metal layer ever created.
The development of the thin superconducting sheets of lead lays the groundwork for future advancements in superconductor technologies.
The superconductors are unique as they can maintain an electrical current indefinitely with no power source. They are used in MRI (Magnetic Resonance Imaging) machines, particle accelerators, quantum interference devices and other applications.
Professor Ken Shih and his colleagues first reported about their creation in the June 5 issue of Science.
"To be able to control this material - to shape it into new geometries - and explore what happens is very exciting," says Shih. "My hope is that this superconductive surface will enable one to build devices and study new properties of superconductivity."
In superconductors, electrons move through the material together in pairs, called Cooper pairs.
One of the innovative properties of Shih's ultra-thin lead is that it confines the electrons to move in two dimensions. Quite uniquely, the lead remains a good superconductor despite the constrained movement of the electrons through the metal.
Shih and his colleagues used advanced materials synthesis techniques to lay the two-atom thick sheet of lead atop a thin silicon surface. The lead sheets are highly uniform with no impurities.
"We can make this film, and it has perfect crystalline structure - more perfect than most thin films made of other materials," says Shih.