Open AccessGrating couplers for broadside input and output coupling of long-range surface plasmons
Author(s) -
Chengkun Chen,
Pierre Berini
Publication year - 2010
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.18.008006
Subject(s) - grating , optics , surface plasmon , surface plasmon polariton , coupling (piping) , broadside , materials science , finite difference time domain method , plasmon , diffraction grating , gaussian beam , ultrasonic grating , optoelectronics , physics , blazed grating , beam (structure) , metallurgy
Metal gratings for in-coupling a Gaussian beam incident from broadside to the long-range surface plasmon polariton (LRSPP) propagating in one direction along a membrane-supported Au slab bounded by air or water are proposed and modeled by the finite-difference time-domain method. Grating couplers for out-coupling the propagating LRSPP into free radiation directed along broadside are also investigated. Short grating designs consisting of a small number of Au bumps yield 15% to 20% in-coupling efficiencies, and about 60% out-coupling efficiencies. LRSPP back-reflections along the membrane waveguide caused by the out-coupling grating are also calculated and discussed.