Physicists Practice ‘Spin Control’ to Improve Information Processing
July 18, 2018 | UC San DiegoEstimated reading time: 2 minutes
Currently, information-processing tools like computers and cell phones rely on electron charge to operate. A team of UC San Diego physicists, however, seeks alternative systems of faster, more energy-efficient signal processing. They do this by using “excitons,” electrically neutral quasiparticles that exist in insulators, semiconductors and in some liquids. And their latest study of excitonic spin dynamics shows functional promise for our future devices.
In their research, Professor Leonid Butov and recent physics PhD graduate Jason Leonard, applied indirect excitons (IXs)—specially designed quasiparticles in a layered semiconductor structure—in Bose-Einstein condensate form. With this condensate of IXs, the scientists discovered that the IXs’ spin coherence was conserved when they traveled over long distance, proving hopeful for more energy-efficient signal processing in the future. The study’s results also presented a way to achieve long-range spin coherence—necessary for efficient and speedy circuits using spin transfer. Their findings were published recently in Nature Communications.
“We measured the exciton phase acquired due to coherent spin precession and observed long-range coherent spin transport in IX condensate,” explained Butov. “Long-range spin transport can be explored for the development of new signal processing based on spins.”
Using a specially crafted optical dilution refrigerator set at a very low temperature—0.1 Kelvin or 459.50 F below zero—Butov and his team transformed the IX gas to a condensate by the frigid temperature to achieve spin coherence at the range of 10 micrometers, a range conducive to the development of high-functioning devices exploring spin transfer.
“We started the project trying to explain a quantum phase shift and ended up with a practical observation of spin transport,” noted Leonard.
While this experiment demonstrated one of the capabilities of IX spin coherence at cryogenic temperatures, Butov’s previous study showed that IXs can exist in semiconductors at room temperature—an important step toward practical application.
These studies were supported by the Department of Energy Office of Basic Energy Sciences (award DE-FG02-07ER46449) and coherence studies by the NSF (grant no. 1640173) and NERC, a subsidiary of SRC, through the SRC-NRI Center for Excitonic Devices.
At UC San Diego our research efforts are designed to change the world for the better—through new medicines, innovative technologies and more that will help address disease, global security, public policy, climate change and more. The Department of Physics in the Division of Physical Sciences is one of the university’s founding departments. The first students to enroll at the university in 1960 were graduate students in physics. Today our graduate program in physics is among the top 20 in the nation.
Suggested Items
KIC’s Miles Moreau to Present Profiling Basics and Best Practices at SMTA Wisconsin Chapter PCBA Profile Workshop
01/25/2024 | KICKIC, a renowned pioneer in thermal process and temperature measurement solutions for electronics manufacturing, announces that Miles Moreau, General Manager, will be a featured speaker at the SMTA Wisconsin Chapter In-Person PCBA Profile Workshop.
The Drive Toward UHDI and Substrates
09/20/2023 | I-Connect007 Editorial TeamPanasonic’s Darren Hitchcock spoke with the I-Connect007 Editorial Team on the complexities of moving toward ultra HDI manufacturing. As we learn in this conversation, the number of shifting constraints relative to traditional PCB fabrication is quite large and can sometimes conflict with each other.
Standard Of Excellence: The Products of the Future
09/19/2023 | Anaya Vardya -- Column: Standard of ExcellenceIn my last column, I discussed cutting-edge innovations in printed circuit board technology, focusing on innovative trends in ultra HDI, embedded passives and components, green PCBs, and advanced substrate materials. This month, I’m following up with the products these new PCB technologies are destined for. Why do we need all these new technologies?
Experience ViTrox's State-of-the-Art Offerings at SMTA Guadalajara 2023 Presented by Sales Channel Partner—SMTo Engineering
09/18/2023 | ViTroxViTrox, which aims to be the world’s most trusted technology company, is excited to announce that our trusted Sales Channel Partner (SCP) in Mexico, SMTo Engineering, S.A. de C.V., will be participating in SMTA Guadalajara Expo & Tech Forum. They will be exhibiting in Booth #911 from the 25th to the 26th of October 2023, at the Expo Guadalajara in Jalisco, Mexico.
Intel Unveils Industry-Leading Glass Substrates to Meet Demand for More Powerful Compute
09/18/2023 | IntelIntel announced one of the industry’s first glass substrates for next-generation advanced packaging, planned for the latter part of this decade.