Oscillatory optical response of an amorphous two-dimensional array of gold nanoparticles.
The optical response of metallic nanoparticle arrays is dominated by localized surface plasmon excitations and is the sum of individual particle contributions modified by interparticle coupling that depends on specific array geometry. We demonstrate a so far unexplored distinct oscillatory behavior of the plasmon peak position, full width at half maximum, and extinction efficiency in large area amorphous arrays of Au nanodisks, which depend on the minimum particle center-to-center distance in the array. Amorphous arrays exhibit short-range order and are completely random at long distances. In our theoretical analysis we introduce a film of dipoles approach, within the framework of the coupled dipole approximation, which describes the array as an average particle surrounded by a continuum of dipoles with surface densities determined by the pair correlation function of the array.
Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden. tomasza@chalmers.se
Tomasz J
TJ
Antosiewicz
S Peter
SP
Apell
Michael
M
Zäch
Igor
I
Zorić
Christoph
C
Langhammer
D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008956:Models, Chemical; D055095:Optics and Photonics / Q000379:methods; D009991:Oscillometry / Q000379:methods*; D020349:Surface Plasmon Resonance
D006046:Gold