Scientists Demonstrate Ultra Fast Magnetite Electrical Switch

If you thought silicon-based transistors were fast, try making electrical switches out of magnetite. Researchers at U.S. Department of Energy’s (DOE) SLAC National Accelerator Laboratory recently demonstrated electrical switching "thousands of times faster than in transistors now in use" using the naturally magnetic mineral, according to team leader Roopali Kukreja, a materials science researcher at Stanford University.

The research team, which published its findings in the latest issue of the journal Nature Materials, fired SLAC’s Linac Coherent Light Source (LCLS) X-ray laser at magnetite samples and found that flipping an on-off electrical switch in the material took a mere 1 trillionth of a second.

"This breakthrough research reveals for the first time the ‘speed limit’ for electrical switching in this material," Kukreja said.

Kukreja and his colleagues said the experiment was a major step forward in understanding electrical structures at the atomic level and working with recently identified electrical "building blocks" called trimerons.

The LCLS experiment demonstrated "how the electronic structure of the sample rearranged into non-conducting ‘islands’ surrounded by electrically conducting regions, which began to form just hundreds of quadrillionths of a second after a laser pulse struck the sample," the researchers said.

The SLAC team said the breakthrough "could drive innovations in the tiny transistors that control the flow of electricity across silicon chips, enabling faster, more powerfulcomputing devices." Building on the way the conducting regions and non-conducting islands are able to coexist, the scientists said next-generation transistors could potentially utilize the electrical pathways created in that process to perform electrical switching orders of magnitude faster than is currently possible with the materials used for semiconductors today.

However, there’s a slight hitch to be overcome before fabbing magnetite computer chips is possible. To lock an electrical charge in place in the material, it has to be chilled to minus 190 degrees Celsius.

Kukreja said the next objective for the team will be to try out electrical switching with "more complex materials and room-temperature applications" through new experiments which "aim to identify exotic compounds and test new techniques to induce the switching and tap into other properties that are superior to modern-day silicon transistors."

The SLAC team said they’ve already begun testing a hybrid material which can perform ultra-fast switching at near room temperature.