IBM scientists used ultra short laser pulses to monitor the evolution of thousands of electron spins that were created simultaneously in a very small spot, said Gian Salis, co-author of the Nature paper and a scientist in the Physics of Nanoscale Systems research group at IBM Research.Usually, such spins find electrons randomly rotating and quickly losing their orientation. In this study, IBM and ETH researchers found, for the first time, how to arrange the spins neatly into a regular stripe-like pattern – the so-called persistent spin helix.
Current methods of generating terahertz radiation involve lasers, thermionic valves and special circuits cooled near absolute zero, often in room-sized apparatuses costing thousands of dollars.
Cornell researchers with Ehsan Afshari, assistant professor of electrical and computer engineering, have developed a new method using the familiar and inexpensive CMOS chip technology, generating power levels high enough for some medical applications.
“It is truly an interdisciplinary team effort,” Zhou says. “The co-existence of photonics with electronics on the chip level shall enable multifunctional, energy-efficient super-chips for applications in computing, communications, sensing, imaging and so on.”