Monday, August 01, 2005

"QUANTUM: One-dimensional wires demo electron split"

Researchers at the Weizmann Institute of Science have experimentally verified a long-postulated possibility for one-dimensional quantum devices. The team fabricated wires so small that they were able to witness electron spin separating from its charge. The observation holds out more hope for the development of spin-based circuits.
"If you were to naively scale down the width of the wires in your device, they would cease to conduct at some point, even if you were able to make them perfect, which you won't," said Ophir Auslaender. The Weizmann Institute postdoctoral researcher was the one who first observed spin separating from charge. "We were able to observe some of these effects because our experiment circumvents some of the experimental barriers," Auslaender said. In the new breed of spintronic devices, digital logic is represented by electron spin rather than charge. In some research centers, experiments have shown that spin can flow and be modified by spintronic logic gates. Without the independent propagation of spin, spintronic devices would be limited-unable to add much functionality to the array of options available to today's circuit designers. Researchers Auslaender and Hadar Steinberg performed the work in the laboratory of professor Amir Yacoby at the Weizmann Institute of Science's Condensed Matter Physics Department.