Event Date
Professor Siyuan Dai
McWane Associate Professor and Ginn Faculty Achievement fellow
Department of Mechanical Engineering, Auburn University
Abstract
Scanning probe optical microscopy offers access to material properties beyond the fundamental diffraction limit in conventional optics. In this talk, I will start by introducing nano-spectroscopic material identification—nano-fingerprinting. Nanoscale composition and heterogeneity of a range of materials, including natural specimens and biomedical devices, can be delicately identified without perturbation. Furthermore, scanning probe optics facilitates the investigation of nanoscale light-matter interactions in quantum materials. A representative topic is the study of confined light-matter waves—polaritons—in van der Waals (vdW) materials. Using the nano-optical apparatus, we have studied various polaritons in vdW materials and their heterostructures, showing unique nanophotonic virtues in reduced dimensions. Notably, weak vertical bonding in vdW systems allows the engineering of polaritonic nano-optics in heterostructures by stacking, twisting, microstructuring, and isotope heterostructuring of the constituent vdW layers. Nano-optical responses in these engineered structures can be tailored to reveal on-demand wavefronts, dispersions, dynamic tunabilities, and mode conversions, among others.
Bio
Siyuan Dai is the McWane Associate Professor and Ginn Faculty Achievement fellow of Materials Science & Engineering in the Department of Mechanical Engineering at Auburn University. He holds a Ph.D. in Physics from University of California, San Diego (2017) and a B.S. degree in Applied Physics from University of Science & Technology of China (2011). In 2018, he was a postdoc research fellow at the University of Texas at Austin. His research expertise and interests are nano-optics and light-matter interactions in quantum materials and nanostructures. He is the recipient of the ACS PRF Doctoral New Investigator Award and the NSF CAREER Award.