A Step Toward Nuclear Spintronic Technologies
June 25, 2015 | University of ChicagoEstimated reading time: 2 minutes
An electronics technology that uses the “spin”—or magnetization—of atomic nuclei to store and process information promises huge gains in performance over today’s electron-based devices. But getting there is proving challenging.
Now, researchers at the University of Chicago’s Institute for Molecular Engineering have made a crucial step toward nuclear spintronic technologies. They have gotten nuclear spins to line themselves up in a consistent, controllable way, and they have done it using a high-performance material that is practical, convenient and inexpensive.
“Our results could lead to new technologies like ultra-sensitive magnetic resonance imaging, nuclear gyroscopes and even computers that harness quantum mechanical effects,” said Abram Falk, the lead author of the report on the research, which was featured as the cover article of the June 17 issue of Physical Review Letters. Falk and colleagues in David Awschalom’s IME research group invented a new technique that uses infrared light to align spins. They did so using silicon carbide, an industrially important semiconductor.
Nuclear spins tend to be randomly oriented. Aligning them in a controllable fashion is usually a complicated and only marginally successful proposition. The reason, explains Paul Klimov, a co-author of the paper, is that “the magnetic moment of each nucleus is tiny, roughly 1,000 times smaller than that of an electron.”
This small magnetic moment means that little thermal kicks from surrounding atoms or electrons can easily randomize the direction of the nuclear spins. Extreme experimental conditions such as high magnetic fields and cryogenic temperatures (-238 degrees Fahrenehit and below) are usually required to get even a small number of spins to line up. In magnetic resonance imaging, for example, only one to 10 out of a million nuclear spins can be aligned and seen in the image, even with a high magnetic field applied.
Using their new technique, Awschalom, the Liew Family Professor in Spintronics and Quantum Information, and his associates aligned more than 99 percent of spins in certain nuclei in silicon carbide. Equally important, the technique works at room temperature—no cryogenics or intense magnetic fields needed. Instead, the research team used light to “cool” the nuclei.
While nuclei do not interact with light themselves, certain imperfections, or “color-centers,” in the SiC crystals do. The electron spins in these color centers can be readily optically cooled and aligned, and this alignment can be transferred to nearby nuclei. Had the group tried to achieve the same degree of spin alignment without optical cooling, they would have had to chill the SiC chip physically to just five millionths of a degree above absolute zero (-459.6 degrees Fahrenheit).
Getting spins to align in room-temperature silicon carbide brings practical spintronic devices a significant step closer, said Awschalom. The material is already an important semiconductor in the high-power electronics and opto-electronics industries. Sophisticated growth and processing capabilities are already mature. So prototypes of nuclear spintronic devices that exploit the IME researchers’ technique may be developed in the near future.
“Wafer-scale quantum technologies that harness nuclear spins as subatomic elements may appear more quickly than we anticipated,” Awschalom said.
Suggested Items
Warm Windows and Streamlined Skin Patches – IDTechEx Explores Flexible and Printed Electronics
04/26/2024 | IDTechExFlexible and printed electronics can be integrated into cars and homes to create modern aesthetics that are beneficial and easy to use. From luminous car controls to food labels that communicate the quality of food, the uses of this technology are endless and can upgrade many areas of everyday life.
Book Excerpt: The Printed Circuit Assembler’s Guide to... Factory Analytics
04/24/2024 | I-Connect007 Editorial TeamIn our fast-changing, deeply competitive, and margin-tight industry, factory analytics can be the key to unlocking untapped improvements to guarantee a thriving business. On top of that, electronics manufacturers are facing a tremendous burden to do more with less. If you don't already have a copy of this book, what follows is an excerpt from the introduction chapter of 'The Printed Circuit Assembler’s Guide to... Factory Analytics: Unlocking Efficiency Through Data Insights' to whet your appetite.
Listen Up! The Intricacies of PCB Drilling Detailed in New Podcast Episode
04/25/2024 | I-Connect007In episode 5 of the podcast series, On the Line With: Designing for Reality, Nolan Johnson and Matt Stevenson continue down the manufacturing process, this time focusing on the post-lamination drilling process for PCBs. Matt and Nolan delve into the intricacies of the PCB drilling process, highlighting the importance of hole quality, drill parameters, and design optimization to ensure smooth manufacturing. The conversation covers topics such as drill bit sizes, aspect ratios, vias, challenges in drilling, and ways to enhance efficiency in the drilling department.
Elevating PCB Design Engineering With IPC Programs
04/24/2024 | Cory Blaylock, IPCIn a monumental stride for the electronics manufacturing industry, IPC has successfully championed the recognition of the PCB Design Engineer as an official occupation by the U.S. Department of Labor (DOL). This pivotal achievement not only underscores the critical role of PCB design engineers within the technology landscape, but also marks the beginning of a transformative journey toward nurturing a robust, skilled workforce ready to propel our industry into the future.
Winner of The Science Show Rakett 69 Receives Incap Scholarship
04/24/2024 | IncapThe winner of the Rakett 69 science show, Andri Türkson, who stood out as an electronics enthusiast, received a scholarship from Incap Estonia, along with an internship opportunity in Saaremaa.