TY - GEN
T1 - Gold nanoparticle absorption under a nanoscale tip illuminated by surface-plasmon polaritons
AU - Huda, Gazi M.
AU - Hastings, J. Todd
PY - 2013
Y1 - 2013
N2 - This research numerically calculated the optical absorption of gold nanoparticles (AuNP) in the presence of metallic (Au) and dielectric (Si) AFM probes, illuminated by a surface plasmon polaritons on an infinite gold substrate. Nanoscale probes localize and enhance the field between the apex of the tip and the particle. However, the absorption of the nanoparticle is not always enhanced; in fact, under a gold tip, the absorption is suppressed for a 50 nm diameter AuNP. After fitting the numerical absorption data with the equation of a driven damped harmonic oscillator (HO), it was found that the AFM tip modifies both the driving force (F0), consisting of the free carrier charge (q) and the driving field (E), and the overall damping of the oscillator (β). The enhancement or suppression of absorption with different tips can be understood in terms of competition between β and F 0. Introducing the metallic tip increases β and decreases F 0, resulting in reduced absorption. Introducing the dielectric tip, although it increases β,it also increases F0, resulting in overall absorption enhancement. Therefore, one most consider both β and F0 to control the absorption of nanoparticles under Surface Plasmon Polaritons.
AB - This research numerically calculated the optical absorption of gold nanoparticles (AuNP) in the presence of metallic (Au) and dielectric (Si) AFM probes, illuminated by a surface plasmon polaritons on an infinite gold substrate. Nanoscale probes localize and enhance the field between the apex of the tip and the particle. However, the absorption of the nanoparticle is not always enhanced; in fact, under a gold tip, the absorption is suppressed for a 50 nm diameter AuNP. After fitting the numerical absorption data with the equation of a driven damped harmonic oscillator (HO), it was found that the AFM tip modifies both the driving force (F0), consisting of the free carrier charge (q) and the driving field (E), and the overall damping of the oscillator (β). The enhancement or suppression of absorption with different tips can be understood in terms of competition between β and F 0. Introducing the metallic tip increases β and decreases F 0, resulting in reduced absorption. Introducing the dielectric tip, although it increases β,it also increases F0, resulting in overall absorption enhancement. Therefore, one most consider both β and F0 to control the absorption of nanoparticles under Surface Plasmon Polaritons.
KW - AFM probe
KW - evanescent wave
KW - finite element method
KW - harmonic oscillator
KW - optical absorption
KW - plasmonics
KW - propagating surface plasmon
UR - http://www.scopus.com/inward/record.url?scp=84878124707&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84878124707&partnerID=8YFLogxK
U2 - 10.1117/12.2002619
DO - 10.1117/12.2002619
M3 - Conference contribution
AN - SCOPUS:84878124707
SN - 9780819493880
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - Physics and Simulation of Optoelectronic Devices XXI
T2 - Physics and Simulation of Optoelectronic Devices XXI
Y2 - 4 February 2013 through 7 February 2013
ER -