University of Houston Cullen College of Engineering researchers are attempting to develop novel magnetic field sensor technology key in the creation of a low-cost system to map magnetic objects quickly and accurately. The development of these cost-efficient, highly-sensitive magnetic nanodevices could have wide-ranging impact on everything from medical diagnostics to national defense.
As it stands, more than 100 million landmines and other ordinances are believed to exist throughout the world, posing an invariable risk to many civilians including the U.S. armed services stationed or fighting abroad. Their immobilization and removal are impeded due to the high cost of detection systems—technology that is currently not sensitive enough.
Stanko Brankovic, assistant professor of electrical engineering, has received a $500,000 grant from the National Science Foundation to fund a transformative concept using electrochemical nanofabrication that would allow the development of devices smaller than 10 nanometers.
The funding is supported through NSF’s GOALI program, which provides grant opportunities for academic and industry partnerships. Brankovic will be working with co-investigators Dmitri Litvinov, associate professor of electrical and computer engineering at UH, Ray Carpenter, professor of materials engineering at Arizona State University and Nils Gokemeijer at Seagate Research.
The team will use ballistic magnetoresistance—the effect of a magnetic field on the ability of electrons to flow between magnetic electrodes—to develop the sensors. Each will consist of two magnetic electrodes connected by nanocontact, which is a tiny wire that will be formed using electrodeposition between the electrodes.
Brankovic predicts that by exposing the sensor to a magnetic field, the flow of electrons through the nanocontact will fluctuate due to the resulting change in the magnetic orientation of the electrodes. The goal—to provide physical evidence of this change on the nanoscale, the result of which might lead to the development of a magnetic field sensor at least a hundred times more sensitive than what is currently available.
“When you reduce the size of the system below a certain point, the electrons go through the nanocontact without any thermal scattering,” said Brankovic. “The result is a much higher sensitivity than anything currently available from existing magnetic field sensors.”
The team will use this phenomenon as an opportunity to investigate the performance of new nanomaterials found in nanoconfined geometry in order to fabricate highly-sensitive, low-cost magnetic field sensor devices. The research may result in the revolutionary development of new sensors that can be utilized in magnetic recording technology, spintronics and medical diagnostics.