Broadband plasmonic microlenses based on patches of nanoholes.
This paper reports a new type of diffractive microlens based on finite-areas of two-dimensional arrays of circular nanoholes (patches). The plasmonic microlenses can focus single wavelengths of light across the entire visible spectrum as well as broadband white light with little divergence. The focal length is determined primarily by the overall size of the patch and is tolerant to significant changes in patch substructure, including lattice geometry and local order of the circular nanoholes. The optical throughput, however, depends sensitively on the patch substructure and is determined by the wavelengths of surface plasmon resonances. This simple diffractive lens design enables millions of broadband plasmonic microlenses to be fabricated in parallel using soft nanolithographic techniques.
Gao
Hanwei
H
Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
Hyun
Jerome K
JK
Lee
Min Hyung
MH
Yang
Jiun-Chan
JC
Lauhon
Lincoln J
LJ
Odom
Teri W
TW