events

excitonics seminar series

abstract

Progress in nanotechnology is fundamentally dependent on tools for observation, measurement and manipulation. Optical techniques are well
established at the macro-scale, but difficult to apply on the nano-scale. This is due to the mismatch between the wavelength of light,
and the dimensions of nanostructures. Optical antennas present an opportunity to bridge these length scales. These plasmonic devices
enable electromagnetic energy to be concentrated into deep sub-wavelength regions. In this presentation, I will discuss several
aspects of optical antennas. I will discuss the realization of optical antennas fabricated on the facets of laser diodes (APL 89, 093120
(2006)). It was shown experimentally that the antenna concentrated light into a ~40*100nm spot, an area ~50 times smaller than the diffraction limit. I will present recent work on the experimental observation of narrow plasmon resonances in gold nanoparticle arrays (APL 93, 181108
(2008)). I will describe recent work on the observation of strong coupling between localized and propagating surface plasmons (Optics
Letters, in press). Lastly, I will discuss related work on the demonstration of Fresnel zone plates as microfabricated optical tweezers
(APL 92, 071112 (2008)).

bio

Ken Crozier is John Loeb Associate Professor of the Natural Sciences at Harvard University. His work has been featured in MIT Technology Review, Newsweek and Laser Focus World. MIT Technology review highlighted optical antennas as being one of The Top 10 Emerging Technologies for 2007. He received his undergraduate degrees in Electrical Engineering and Physics at the University of Melbourne, Australia. He was awarded the L.R. East Medal (university medal in engineering) by the University of Melbourne. He received his PhD in Electrical Engineering from  Stanford University in 2003 under Professors Calvin Quate and Gordon Kino. He was a recipient of an NSF CAREER award in 2008.