Skip to main content

Magnetic topological insulators are 1,000 times more energy-efficient for switching

Topological insulators are an emerging class of materials that act as both insulators and conductors, and could potentially be used in smartphones, computers and other electronic devices.
A research team at the UCLA Henry Samueli School of Engineering and Applied Science has developed a new class of topological insulators in which one of two layers is magnetized. The advance could lead to the development of much more energy-efficient big-data processing systems and ultra-low power electronics.
Led by Kang Wang, the Raytheon Professor of Electrical Engineering at UCLA and the study's principal investigator, the team demonstrated for the first time that the new topological insulators can be electrically "switched" to make them significantly more energy-efficient than current devices. The research was published April 28 in the journal Nature Materials.
"We are very excited about this important result with the new topological insulators, which should lead to the advancement of future low-power, green electronics," Wang said.
The interiors of topological insulators prevent the flow of electrical currents, but their surfaces allow a current to move with very little resistance. Perhaps most importantly, their surfaces enable the transport of spin-polarized electrons while preventing the "scattering" of electrons that causes energy to be dissipated and wasted.
The  created at UCLA comprises two layers, one of which contains chromium, a magnetic element. An electrical current that drives spin-polarized electrons can switch the up-down polarity of the magnetic chromium atoms. This switching is what enables the device to write memory or perform calculations.
Most significantly, the new two-layer structure uses 1,000 times less energy to switch polarity than comparable memory structures.
"This is the first time that topological insulators have been incorporated in a magnetic structure that can be efficiently switched, and is perhaps the first demonstration of potential applicable devices based on topological insulators," said Yabin Fan, the paper's lead author and a UCLA graduate student in .
More information: "Magnetization switching through giant spin–orbit torque in a magnetically doped topological insulator heterostructure." Yabin Fan, et al. Nature Materials (2014) DOI: 10.1038/nmat3973. Received 03 December 2013 Accepted 02 April 2014 Published online 28 April 2014

Comments

Post a Comment

Popular posts from this blog

Where the Swastika Was Found 12,000 Years Before Hitler Made Us Uncomfortable About I

Minoan pottery from Crete. The Minoan civilization flourished from 3,000 to 1,100 B.C. (Agon S. Buchholz/Wikimedia Commons) ) Swastika from a 2nd century A.D. Roman mosaic. (Maciej Szczepańczyk/Wikimedia Commons A srivatsa (swastika) sign at Nata-dera Temple, Japan. (Cindy Drukier/Epoch Times) From the Sican/Lambayeque civilization in Peru, which flourished 750 to 1375 A.D. (Wikimedia Commons) Ancient Macedonian helmet with swastika marks, 350-325 B.C., found at Herculanum. (Cabinet des Medailles, Paris/Wikimedia Commons) A Buddha statue on Lantau Island, Hong Kong with a swastika symbol on the chest. (Shutterstock*) A 3,000-year-old necklace found in the Rasht Province of Iran. (Wikimedia Commons) The aviator Matilde Moisant(1878-1964) wearing a swastika medallion in 1912; the symbol was popular as a good luck charm with early aviators. (Wikimedia Commons) A mandala-like swastika, composed of Hebrew letters and surrounded by a circle and a mystica...
Post a Comment
Read more

There’s a Previously Undiscovered Organ in Your Body, And It Could Explain How Cancer Spreads

Ever heard of the interstitium? No? That’s OK, you’re not alone  —  scientists hadn’t either. Until recently. And, hey, guess what  —  you’ve got one! The interstitium is your newest organ. Scientists identified it for the first time because they are better able to observe living tissues at a microscopic scale, according to a recent study published  in  Scientific Reports , Scientists had long believed that connective tissue surrounding our organs was a thick, compact layer. That’s what they saw when they looked at it in the lab, outside the body, at least. But in a routine endoscopy (exploration of the gastrointestinal tract), a micro camera revealed something unexpected: When observed in a living body, the connective tissue turned out to be “an open, fluid-filled space supported by a lattice made of thick collagen bundles,” pathologist and study author Neil Theise  told  Research Gate . This network of channels is present throughout ...
Post a Comment
Read more
Missing link in metal physics explains Earth's magnetic field Conception of Earth's core overlaid by the electronic structure of iron; the width (fuzziness) of the lines results from the electron-electron scattering. Image courtesy of Ronald Cohen. Credit: Ronald Cohen Earth's magnetic field is crucial for our existence, as it shields the life on our planet's surface from deadly cosmic rays. It is generated by turbulent motions of liquid iron in Earth's core. Iron is a metal, which means it can easily conduct a flow of electrons that makes up an electric current. New findings from a team including Carnegie's Ronald Cohen and Peng Zhang shows that a missing piece of the traditional theory explaining why metals become less conductive when they are heated was needed to complete the puzzle that explains this field-generating process. Their work is published in  Nature . The center of the Earth is very hot, and the flow of heat from the planet's center to...
Post a Comment
Read more