Condensed-Matter Physics & Materials Science Seminar

Eugene U. Donev
Postdoctoral scholar: Dept of Electrical & Computer Engineering, University of Kentucky, Lexington, KY
Ph.D.: Dept of Physics & Astronomy, Vanderbilt University, Nashville, TN
Nanoscale science and engineering seek to understand and control the properties of objects with sizes
ranging roughly from a few nanometers to a few micrometers. At such length scales, some properties like
the optical responses of noble metals change dramatically; others vary more subtly with size, like the
stability of one phase of a material against transforming into another (e.g., solid-solid phase transitions);
and there are also effects unique to the nanoscale regime, such as the confinement and propagation of
light at subwavelength dimensions. From an engineering perspective, the development of novel
nanofabrication methods enables technological applications while at the same time highlighting certain
gaps in our understanding of nanoscale phenomena.
In this talk I will show examples of my work in applied optics and materials physics, in particular some
unique approaches to nanoplasmonics and the nanofabrication of materials. One such approach combines
the thermally-driven semiconductor-to-metal (SMT) phase transition of a prototypical correlated-electron
material, vanadium dioxide (VO2), to control the plasmonic behavior (i.e., collective electron oscillations)
of noble-metal nanostructures: for instance, to modulate the so-called “extraordinary optical transmission”
(EOT) through gold or silver thin films perforated by arrays of subwavength holes. Conversely, another
example exploits the amplification of local electric fields around plasmonic nanoparticles to study sizedependent
effects in the monoclinic-to-rutile structural phase transition (SPT) of VO2, as revealed by
surface-enhanced Raman scattering (SERS). On the nanofabrication side, I will describe a novel
technique for direct-write patterning of metallic nanostructures of