The US Department of Energy has awarded a Colorado State University physicist a five-year, $762,000 Early Career Award to improve scientific understanding of spin dynamics in magnetic materials.
Kristen Buchanan, an assistant professor in the Department of Physics, is one of only three Colorado scientists among the 68 awardees for 2012 and the only recipient at Colorado State University.
Buchanan will use light to study dynamic processes in nanoscale magnets. Spin waves can be imagined as ripples in the magnetic state of a material and light will scatter from these ripples. The scattering process is inelastic, which means that the light loses or gains a small amount of energy in the process. In other words, there is a small shift in the energy, and consequently the color of the light after it scatters provides information about the nature of the spin excitations present in the sample.
To measure the color shift, Buchanan uses a sensitive interferometer, an instrument that uses the same principle that gives rise to the colorful sheen observed in soap bubbles and on thin films of oil on a puddle after a rainstorm. She and her students have built a microscope to use this light scattering technique to study dynamic processes in small patterned magnetic structures to improve their understanding of how spin waves travel and interact.
Dynamic excitations in ferromagnetic materials (spin waves) play a key role in a range of intriguing physics phenomena. They are also important for the advancement of technology in spintronics devices, storage media and medical applications. Buchanan’s research on the spin excitations in magnetic elements will improve overall understanding of the physics of magnetism and lead to innovations in the role of magnets in processing as well as storing information in new energy-efficient devices.
Buchanan’s grant, “Spin Wave Interactions in Metallic Ferromagnets”, was selected by DOE’s Office of Basic Energy Sciences.
“Dr. Buchanan is a tremendous asset to this department and a leader in her field,” said John Harton, chair of the Department of Physics at Colorado State. “We’re pleased, but not surprised, that she has received this prestigious grant.”
Buchanan is part of the Magnetic Materials & Applied Magnetics Laboratory in the College of Natural Sciences. The team researches dynamic properties of magnets, how they perform on the nanoscale, and how to improve measurement techniques to explore these materials. Their approaches include studies of ultra-high speed spin reversal and high resolution images of waves, spin waves, in nanoscale thin magnetic film structures.
Buchanan is also the lead principal investigator on a $962,000 US Department of Commerce grant to improve tiny magnets in information-storage devices such as computers and generally improve electronic communication. She works with Mingzhong Wu and Carl Patton, also physics professors at CSU, on that grant. Buchanan’s research program is also supported by the National Science Foundation, and she hosts high school students in the laboratory each summer as apprentices, a program that is supported by the Academy of Applied Sciences to help get students interested in pursuing careers in science.