57th Annual Report on Research 2012 Under Sponsorship of the ACS Petroleum Research Fund

Objective and summary of achievements: The objective of the proposal is to understand the nano-structure dependence of metal and semi-conductor film using electrodynamics theory. We, for the first time, found that a Fano shape resonance peak can be found in a silver nanoparticle rod.

1. Impact to the PI's research

The award helps the early career development of the PI and members in the PI's group. Six peer-reviewed papers were published as a result of the award in the year 2011-2012. The achievements from the projects had been used as preliminary results for external funding applications from agencies, including NSF and DOE.

2. Educational impact

Two graduate students and one visiting scholar were involved in the project. Graduate student Haining Wang and Jennifer Reed calculated Fano resonance structure in a single silver rod. Haining Wang and Jennifer Reed also finished several collaborative projects with groups of Dr. Zhang at the University of California at Santa Cruz and Dr. Zhang from the Mississippi State University as well as Dr. Su in the Nanotechnology Center at the University of Central Florida.

3. Research achievements

Using electrodynamics tools, we investigated the optical properties of a single silver rod. We found that when the rod length is larger than 200 nm, a Fano shape resonance can be observed at wavelengths of around 480 nm. We examined the mechanism leading to the Fano resonance and found that the asymmetric shape can be caused by the interference between two excited dipoles or between one excited dipole and one quadrupole. The results are very helpful for controllable wave propagation in a nano-device.