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Title: Plasmon resonance-based optical trapping of single and multiple Au nanoparticles.

Abstract

The plasmon resonance-based optical trapping (PREBOT) method is used to achieve stable trapping of metallic nanoparticles of different shapes and composition, including Au bipyramids and Au/Ag core/shell nanorods. In all cases the longitudinal plasmon mode of these anisotropic particles is used to enhance the gradient force of an optical trap, thereby increasing the strength of the trap potential. Specifically, the trapping laser is slightly detuned to the long-wavelength side of the longitudinal plasmon resonance where the sign of the real component of the polarizability leads to an attractive gradient force. A second (femtosecond pulsed) laser is used to excite two-photon fluorescence for detection of the trapped nanoparticles. Two-photon fluorescence time trajectories are recorded for up to 20 minutes for single and multiple particles in the trap. In the latter case, a stepwise increase reflects sequential loading of single Au bipyramids. The nonlinearity of the amplitude and noise with step number are interpreted as arising from interactions or enhanced local fields among the trapped particles and fluctuations in the arrangements thereof.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
National Science Foundation (NSF); USDOE Office of Science (SC)
OSTI Identifier:
962060
Report Number(s):
ANL/CNM/JA-59763
Journal ID: ISSN 1094-4087; TRN: US0903536
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Opt. Express; Journal Volume: 15; Journal Issue: 19 ; 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLITUDES; DETECTION; FLUCTUATIONS; FLUORESCENCE; LASERS; PLASMONS; POLARIZABILITY; RESONANCE; TRAJECTORIES; TRAPPING

Citation Formats

Toussaint, K. C., Liu, M., Pelton, M., Pesic, J., Guffey, M., Guyot-Sionnest, P., Scherer, N. F., and Univ. of Chicago. Plasmon resonance-based optical trapping of single and multiple Au nanoparticles.. United States: N. p., 2007. Web. doi:10.1364/OE.15.012017.
Toussaint, K. C., Liu, M., Pelton, M., Pesic, J., Guffey, M., Guyot-Sionnest, P., Scherer, N. F., & Univ. of Chicago. Plasmon resonance-based optical trapping of single and multiple Au nanoparticles.. United States. doi:10.1364/OE.15.012017.
Toussaint, K. C., Liu, M., Pelton, M., Pesic, J., Guffey, M., Guyot-Sionnest, P., Scherer, N. F., and Univ. of Chicago. Mon . "Plasmon resonance-based optical trapping of single and multiple Au nanoparticles.". United States. doi:10.1364/OE.15.012017.
@article{osti_962060,
title = {Plasmon resonance-based optical trapping of single and multiple Au nanoparticles.},
author = {Toussaint, K. C. and Liu, M. and Pelton, M. and Pesic, J. and Guffey, M. and Guyot-Sionnest, P. and Scherer, N. F. and Univ. of Chicago},
abstractNote = {The plasmon resonance-based optical trapping (PREBOT) method is used to achieve stable trapping of metallic nanoparticles of different shapes and composition, including Au bipyramids and Au/Ag core/shell nanorods. In all cases the longitudinal plasmon mode of these anisotropic particles is used to enhance the gradient force of an optical trap, thereby increasing the strength of the trap potential. Specifically, the trapping laser is slightly detuned to the long-wavelength side of the longitudinal plasmon resonance where the sign of the real component of the polarizability leads to an attractive gradient force. A second (femtosecond pulsed) laser is used to excite two-photon fluorescence for detection of the trapped nanoparticles. Two-photon fluorescence time trajectories are recorded for up to 20 minutes for single and multiple particles in the trap. In the latter case, a stepwise increase reflects sequential loading of single Au bipyramids. The nonlinearity of the amplitude and noise with step number are interpreted as arising from interactions or enhanced local fields among the trapped particles and fluctuations in the arrangements thereof.},
doi = {10.1364/OE.15.012017},
journal = {Opt. Express},
number = 19 ; 2007,
volume = 15,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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