Role of quasicylindrical waves and surface plasmon polaritons on beam shaping with resonant nanogratings in the infrared
Gan, Choon How
Nash, Geoffrey R.
Physical Review B - Condensed Matter and Materials Physics
American Physical Society
Copyright © 2014 American Physical Society
The role of quasicylindrical waves and surface plasmon polaritons in beam shaping with resonant nanogratings is investigated. It is shown that the field on the grating surface can be strongly influenced by plasmons and quasicylindrical waves in the infrared. A method that combines far-field measurements with the fast Fourier transform to map the field amplitude at the grating surface is demonstrated. For samples with a small degree of geometric asymmetry, it is shown that the imaginary part of the transform (with null zeroth-order component) can better map the amplitude of the resonant surface waves than the full complex-valued transform. Our results will impact the study, design, and footprint of resonant nanogratings. © 2014 American Physical Society.
Engineering and Physical Sciences Research Council (EPSRC)
Vol. 89, Iss. 20, 201415(R)