Featured Research

from universities, journals, and other organizations

Speed limit set for ultrafast electrical switch

Date:
July 28, 2013
Source:
DOE/SLAC National Accelerator Laboratory
Summary:
Researchers have clocked the fastest-possible electrical switching in magnetite, a naturally magnetic mineral. Their results could drive innovations in the tiny transistors that control the flow of electricity across silicon chips, enabling faster, more powerful computing devices.

An optical laser pulse (red streak from upper right) shatters the ordered electronic structure (blue) in an insulating sample of magnetite, switching the material to electrically conducting (red) in one trillionth of a second.
Credit: Greg Stewart/SLAC

Researchers from the U.S. Department of Energy's (DOE) SLAC National Accelerator Laboratory have clocked the fastest-possible electrical switching in magnetite, a naturally magnetic mineral. Their results could drive innovations in the tiny transistors that control the flow of electricity across silicon chips, enabling faster, more powerful computing devices.

Scientists using SLAC's Linac Coherent Light Source (LCLS) X-ray laser found that it takes only 1 trillionth of a second to flip the on-off electrical switch in samples of magnetite, which is thousands of times faster than in transistors now in use. The results were published July 28 in Nature Materials.

"This breakthrough research reveals for the first time the 'speed limit' for electrical switching in this material," said Roopali Kukreja, a materials science researcher at SLAC and Stanford University who is a lead author of the study.

The LCLS experiment also showed researchers 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 study shows how such conducting and non-conducting states can coexist and create electrical pathways in next-generation transistors.

Scientists first hit each sample with a visible-light laser, which fragmented the material's electronic structure at an atomic scale, rearranging it to form the islands. The laser blast was followed closely by an ultrabright, ultrashort X-ray pulse that allowed researchers to study, for the first time, the timing and details of changes in the sample excited by the initial laser strike.

By slightly adjusting the interval of the X-ray pulses, they precisely measured how long it took the material to shift from a non-conducting to an electrically conducting state, and observed the structural changes during this switch.

Scientists had worked for decades to resolve this electrical structure at the atomic level, and just last year another research team had identified its building blocks as "trimerons" -- formed by three iron atoms that lock in the charges. That finding provided key insights in interpreting results from the LCLS experiment.

The magnetite had to be cooled to minus 190 degrees Celsius to lock its electrical charges in place, so the next step is to study more complex materials and room-temperature applications, Kukreja said. Future experiments will 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 researchers have already conducted follow-up studies focusing on a hybrid material that exhibits similar ultrafast switching properties at near room temperature, which makes it a better candidate for commercial use than magnetite.

Hermann Dürr, the principal investigator of the LCLS experiment and senior staff scientist for the Stanford Institute for Materials and Energy Sciences (SIMES), said there is a major global effort underway to go beyond modern semiconductor transistors using new materials to satisfy demands for smaller and faster computers, and LCLS has the unique ability to home in on processes that occur at the scale of atoms in trillionths and quadrillionths of a second.

While magnetite's basic magnetic properties have been known for thousands of years, the experiment shows how much still can be learned about the more exotic electronic properties of magnetite and other more complex materials using LCLS, Dürr said.


Story Source:

The above story is based on materials provided by DOE/SLAC National Accelerator Laboratory. Note: Materials may be edited for content and length.


Journal Reference:

  1. S. de Jong, R. Kukreja, C. Trabant, N. Pontius, C. F. Chang, T. Kachel, M. Beye, F. Sorgenfrei, C. H. Back, B. Bräuer, W. F. Schlotter, J. J. Turner, O. Krupin, M. Doehler, D. Zhu, M. A. Hossain, A. O. Scherz, D. Fausti, F. Novelli, M. Esposito, W. S. Lee, Y. D. Chuang, D. H. Lu, R. G. Moore, M. Yi, M. Trigo, P. Kirchmann, L. Pathey, M. S. Golden, M. Buchholz, P. Metcalf, F. Parmigiani, W. Wurth, A. Föhlisch, C. Schüßler-Langeheine, H. A. Dürr. Speed limit of the insulator–metal transition in magnetite. Nature Materials, 2013; DOI: 10.1038/nmat3718

Cite This Page:

DOE/SLAC National Accelerator Laboratory. "Speed limit set for ultrafast electrical switch." ScienceDaily. ScienceDaily, 28 July 2013. <www.sciencedaily.com/releases/2013/07/130728134053.htm>.
DOE/SLAC National Accelerator Laboratory. (2013, July 28). Speed limit set for ultrafast electrical switch. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2013/07/130728134053.htm
DOE/SLAC National Accelerator Laboratory. "Speed limit set for ultrafast electrical switch." ScienceDaily. www.sciencedaily.com/releases/2013/07/130728134053.htm (accessed July 30, 2014).

Share This




More Matter & Energy News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Britain Testing Driverless Cars on Roadways

Britain Testing Driverless Cars on Roadways

AP (July 30, 2014) — British officials said on Wednesday that driverless cars will be tested on roads in as many as three cities in a trial program set to begin in January. Officials said the tests will last up to three years. (July 30) Video provided by AP
Powered by NewsLook.com
China's Drone King Says the Revolution Depends on Regulators

China's Drone King Says the Revolution Depends on Regulators

Reuters - Business Video Online (July 30, 2014) — Comparing his current crop of drones to early personal computers, DJI founder Frank Wang says the industry is poised for a growth surge - assuming regulators in more markets clear it for takeoff. Jon Gordon reports. Video provided by Reuters
Powered by NewsLook.com
3Doodler Bring 3-D Printing to Your Hand

3Doodler Bring 3-D Printing to Your Hand

AP (July 30, 2014) — 3-D printing is a cool technology, but it's not exactly a hands-on way to make things. Enter the 3Doodler: the pen that turns you into the 3-D printer. AP technology writer Peter Svensson takes a closer look. (July 30) Video provided by AP
Powered by NewsLook.com
Climate Change Could Cost Billions, According To White House

Climate Change Could Cost Billions, According To White House

Newsy (July 29, 2014) — A report from the White House warns not curbing greenhouse gas emissions could cost the U.S. billions. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

More Coverage


Picosecond Accurate Slow-Motion Confirms Oxide Materials Exhibit Considerably Faster Switching Properties Than Do Semi-Conductors

July 30, 2013 — Scientists have observed the switching mechanism from a non-conducting to a conducting state in iron oxide (specifically, magnetite) with previously unrealized precision. This switching mechanism -- ... read more
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins