2009 APS March Meeting
Volume 54, Number 1
Monday–Friday, March 16–20, 2009;
Pittsburgh, Pennsylvania
Session T2: Electron, Exciton and Phonon Interactions in Nanoparticles
2:30 PM–5:30 PM,
Wednesday, March 18, 2009
Room: Spirit of Pittsburgh Ballrom BC
Sponsoring
Units:
DCMP DMP
Chair: Phillippe Guyot-Sionnest, University of Chicago
Abstract ID: BAPS.2009.MAR.T2.5
Abstract: T2.00005 : Exciton-plasmon interactions and energy transfer in nanoparticles*
4:54 PM–5:30 PM
Preview Abstract
Abstract
Author:
Alexander Govorov
(Ohio University)
Energy transfer between optically-excited nanocrystals coupled by
the
Coulomb interaction can be very efficient. The interaction of
excitons and
plasmons in nanocrystals leads to several effects: energy
transfer between
nanoparticles (NPs), electromagnetic enhancement, reduced exciton
diffusion
in nanowires (NWs), exciton energy shifts, and interference and
non-linear
phenomena [1-3]. Using kinetic equations for excitons, we model
exciton
transport in a NW and explain the origin of the blue shift of
exciton
emission observed in the recent experiments on hybrid NW-NP
assemblies [2].
We also model artificial light-harvesting complexes composed of
chlorophylls, bacterial reaction centers, and NPs [3]. Using
superior
optical properties of metal and semiconductor NPs, one can
strongly enhance
the efficiency of light harvesting [3]. An interaction between a
discrete
state of exciton and a continuum of plasmonic states can give
rise to
interference effects (Fano-like asymmetric resonances). These
interference
effects greatly enhance visibility of relatively weak exciton
signals and
can be used for spectroscopy of single nanoparticle and
molecules. In the
nonlinear regime, the Fano effect becomes strongly amplified [4]. In
conclusion, our theory explains present experimental results and
also
provides motivation for future experiments and applications.
Potential
applications of dynamical exciton-plasmon systems include sensors
and
light-harvesting. The above theoretical studies were performed in
collaboration with several groups [1-4].
\\[4pt]
[1] A. O. Govorov, G. W. Bryant, W. Zhang, T. Skeini, J. Lee,
N. A. Kotov, J. M. Slocik, and R. R. Naik, Nano Letters
\textbf{6}, 984 (2006).\\[0pt]
[2] J. Lee, P. Hernandez, J. Lee, A. Govorov, and N. Kotov,
Nature Materials \textbf{6}, 291 (2007).\\[0pt]
[3] A. O. Govorov and I. Carmeli, Nano Lett. \textbf{7}, 620
(2007); S. Mackowski, S. W\"{o}rmke, A.J. Maier, T.H.P.
Brotosudarmo, H. Harutyunyan, A. Hartschuh, A.O. Govorov, H.
Scheer, C. Br\"{a}uchle, Nano Lett.~\textbf{8}, 558 (2008). \\[0pt]
[4] M. Kroner, A. O. Govorov, S. Remi, B. Biedermann, S. Seidl,
A. Badolato, P. M. Petroff, W. Zhang, R.Barbour, B. D. Gerardot,
R. J. Warburton, and K. Karrai, Nature \textbf{451}, 311 (2008).
*Supported by NSF and Air Force Research Labs.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2009.MAR.T2.5