Mystery of High-Temperature Superconductors Solved
ZPEnergy
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An experimental mystery – the origin of the insulating state in a class of materials known as doped Mott insulators – has been solved by researchers at the University of Illinois at Urbana-Champaign. The solution helps explain the bizarre behavior of doped Mott insulators, such as high-temperature copper-oxide superconductors.
In a paper published in the Nov. 2 issue of the journal Physical Review Letters, physics professor Philip Phillips and graduate student Ting-Pong Choy show that lightly doped Mott insulators are, in fact, still insulators.
The scientists’ theoretical results confirm previous experimental findings obtained by other researchers. Unlike low-temperature superconductors, which are metals, high-temperature superconductors are insulators in their normal state.
This has puzzled scientists, because half of the electron states are empty. When Mott insulators are lightly doped with holes – thereby creating even more places for electrons to occupy – the material still refuses to conduct.
Strong electron interaction is the key to understanding doped Mott insulators, Phillips said. The insulating state is not caused by disorder, exotic excitations or something external to the system.
Dec 03, 2005
ZPEnergy
_______
An experimental mystery – the origin of the insulating state in a class of materials known as doped Mott insulators – has been solved by researchers at the University of Illinois at Urbana-Champaign. The solution helps explain the bizarre behavior of doped Mott insulators, such as high-temperature copper-oxide superconductors.
In a paper published in the Nov. 2 issue of the journal Physical Review Letters, physics professor Philip Phillips and graduate student Ting-Pong Choy show that lightly doped Mott insulators are, in fact, still insulators.
The scientists’ theoretical results confirm previous experimental findings obtained by other researchers. Unlike low-temperature superconductors, which are metals, high-temperature superconductors are insulators in their normal state.
This has puzzled scientists, because half of the electron states are empty. When Mott insulators are lightly doped with holes – thereby creating even more places for electrons to occupy – the material still refuses to conduct.
Strong electron interaction is the key to understanding doped Mott insulators, Phillips said. The insulating state is not caused by disorder, exotic excitations or something external to the system.
Dec 03, 2005
