Probing Thermophysical Properties of Micro/Nanostructured Materials Using Ultrafast Pump

Friday, November 4 • 2:30 PM – UTEB, Rm. 175

Probing Thermophysical Properties of Micro/Nanostructured Materials Using Ultrafast Pump- Probe Technique

xiaojia-xj-wang

Xiaojia “XJ” Wang

Benjamin Mayhugh Assistant Professor of Mechanical Engineering University of Minnesota, Minneapolis, MN

Abstract: Micro/nanostructured materials behave differently from their macroscale counterparts with regards to thermal energy transport at short time and length scales. The engineering of micro/nanostructures to tailor thermal properties for energy conversion has become an emerging field in thermal science. One of the grand challenges in this area is to achieve sufficient spatial and temporal resolutions for accurate thermal measurements of these materials. This talk will emphasize how ultrafast pump-probe technique, Time-Domain Thermoreflectance (TDTR) and its upgraded version, Time-Resolved Magneto-Optical Kerr Effect (TR- MOKE), can be used to probe thxiaojia-xj-wang2ermal properties with microscale spatial resolution and sub-picosecond temporal resolution. Examples include: 1) TR-MOKE as a novel way to explore the origins of the anisotropic thermal transport in black phosphorus with enhanced measurement sensitivity; and 2) nanoparticle-assisted localized heating for probing interfacial thermal resistance at nanometer scales.

Biographical Sketch: Dr. Xiaojia Wang started her official appointment as an assistant professor in the Department of Mechanical Engineering at the University of Minnesota, Twin Cities in 2014. Prior to this, she was a postdoctoral research associate in the Department of Materials Science and Engineering at the University of Illinois at Urbana-Champaign. She received her Ph.D. in Mechanical Engineering from the Georgia Institute of Technology in 2011, and her M.S. in 2007 and B.S. in 2004 from Xi’an Jiaotong University, China, all in Mechanical Engineering. Her current research focuses on utilizing ultrafast optical techniques to characterize thermal transport in micro/nanostructured materials and across material interfaces, and tailoring the radiative properties of micro/nanostructures for energy conversion and harvesting. For details, please visit her research group website: http://www.me.umn.edu/labs/mnttl/

For additional information, please contact Prof. Michael T. Pettes at (860) 486-2855, michael.pettes@uconn.edu or Laurie Hockla at (860) 486-2189, hockla@engr.uconn.edu