The key to making computers and other electronics smaller, faster and less expensive lies in overcoming the limitations of existing materials. University of Nebraska-Lincoln physicist Xia Hong said she believes her research on nanoscale materials will help break through current barriers.
Hong, assistant professor of physics and astronomy and a researcher in UNL's Materials Research Science and Engineering Center, earned a five-year, $600,000 Faculty Early Career Development Program Award this spring from the National Science Foundation to continue her research. Also known as a CAREER award, it is NSF's most prestigious award for outstanding pre-tenure faculty to help them develop as teacher-scholars and researchers.
For decades, scientists have been squeezing more power out of today's silicon-based electronics, which are approaching the material's fundamental limits. To continue advancing, researchers are exploring existing materials for unique properties at the nano-level and fabricating new nanomaterials with multifunctional properties. Many materials exhibit unusual physical, chemical or biological properties at the nanoscale that are not found at the larger macro level.
With her award, Hong will combine two oxides to create a multiferric nanomaterial with both magnetic and ferroelectric properties. Ferroelectric materials have positive and negative polarization directions. Applying electricity can reverse the polarization. In a multiferric material, electricity also can control magnetism.
Current hard drives and other data storage devices rely on magnetism, which limits their storage density, or capacity, and requires lots of energy to operate. In contrast, ferroelectric-based devices enable much higher density storage. Storing data with an electric charge alone or using electricity to manipulate magnetic signal would be more energy-efficient and allow greater storage capacity in a smaller space.
Hong said she believes it will take one to two years to fabricate the multiferric nanostructure. Then, using cutting-edge techniques, she will study the new material's characteristics. Her research promises to advance the understanding of magnetoelectric coupling and could lead to novel materials and devices.
The grant allows Hong to purchase equipment and hire graduate students and post-doctoral graduates.
The expertise of other faculty in UNL's NSF-funded Materials Research Science and Engineering Center and its focus on nanoscale magnetism and magnetoelectric interfaces aid her research, Hong said.
"My research is very complementary to the existing efforts here," she said. "There is a lot of collaboration. We need a theoretical point of view to understand the new properties we are studying."
Through the grant, Hong also is continuing her interest in making physics accessible to young people, particularly girls. For the educational component of her CAREER award, she will use her drawing skills to develop educational cartoons.
"Many people think physics is very difficult," Hong said. “I thought it was a good idea to use a teenage girl's point of view to illustrate physics principles, not using extensive math equations, but how they operate in real life, to make physics more likable."