A superbly energy-efficient microprocessor that merely consumes a tiny fraction of the power of today’s microprocessors is tough to comprehend. However, one day, using nanomagnets, it could be possible.
Scanning electron microscope image of nanomagnets of various sizes (left) and magnetic force microscope image (right) of magnetization orientation of an array of nanomagnets. Figure courtesy of Jayasimha Atulasimha, Ph.D./VCU.
Such chips could ultimately be used in medical devices implanted in the body, face recognition systems, structural health monitoring systems embedded in buildings or even wearable electronics, such as Google’s augmented reality glasses.
Researchers such as Jayasimha Atulasimha, Ph.D., assistant professor of mechanical and nuclear engineering in the Virginia Commonwealth University School of Engineering, and his team are steadily advancing nanomagnetic logic.
But first they must troubleshoot an important glitch – the high error rate that is found in nanomagnetic logic systems.
Supriyo Bandyopadhyay, Ph.D.
In 2010, Atulasimha, together with collaborator, Supriyo Bandyopadhyay, Ph.D., commonwealth professor of electrical and computer engineering in the VCU School of Engineering, found that multiferroic nanomagnets switched with electrically generated strain (termed as “straintronics”) could be a far more energy-efficient switch – in fact, 1,000 times more efficient – than a transistor.
“However, it turns out that nanomagnetic logic is extremely error-prone at room temperature, because thermal fluctuations can seriously disrupt the switching process,” said Atulasimha.
The research community is grappling with this current Achilles heel for nanomagnetic devices.
To address this thorny problem, Atulasimha has been awarded a five-year National Science Foundation CAREER Award, one of the foundation’s most prestigious awards, to develop sophisticated modeling approaches and use state-of-the art experimental techniques, some of which are so specialized that they are available in only one to two national laboratories. The aim is to understand the fundamental reasons for the problem and to develop error mitigation strategies to solve it.
According to Atulasimha, research will explore a host of solutions, ranging from innovative clocking strategies to error-tolerant device architectures and perhaps even the use of new physical device concepts, such as switching magnetization with light.
In addition to these ongoing research efforts, Atulasimha will help with education efforts in the area of nanomagnetics, including the creation of a graduate course on nanoscale magnetism with an emphasis on nanomagnetic computing. Through the Richmond Area Program for Minorities in Engineering, a summer research program geared to minority high school students will be hosted in Atulasimha’s lab. Hands-on workshops for K-12 coordinated by the Math Science Innovation Center – in schools that traditionally have low representations in science fairs - will be designed to explain nanomagnetic memory and logic. The knowledge will be transferred to teachers as well.
Since coming to VCU in 2008, Atulasimha’s research has been supported by three grants from the National Science Foundation, one from the Nanoelectronics Research Initiative (NRI) as a gift from the Semiconductor Research Corporation and a VCU Presidential Research Incentive Program (PRIP) award with his share of the funding from these grants (including funds promised under the NSF CAREER grant) totaling approximately $1 million.
In July 2012, he was appointed to the Qimonda Endowed Professorship for his exemplary contributions to research, teaching and public service.
The NSF Faculty Early Career Development program supports activities of teacher-scholars who integrate research and education.