Perhaps you know the answer (to this question) already.<\/p>\n
I have read a paper discussing coupling of a plane wave to 2D grating with a new caveat; two plane waves are incident (with different oblique angles to the normal direction) on a horizontal plane containing the 2D plasmonic grating (parallel lines of thin gold lines with the unit cell consisting of individual elements with difference phases providing a linear phase gradient along a specific direction). The plane waves interfer to generate diffraction pattern with spacing similar to the period of the plasmonic grating. The interference pattern (of the two plane waves) moves along the 2D plane (of the plasmonic grating) with time (due to slight differences in their frequencies). The k-vector component (on the horizental plane) is cancelled with an opposite phase gradient of the grating lines within the unit cell. This is called space-time coupling of the plane waves to 2D plasmonic grating. Can you provide insights on how to simulate this configuration in Ansys Lumerical FDTD:<\/p>\n
1- two plane waves with two distinct frequencies (slight offset) imging on a surface in an angle to normal:<\/p>\n
i- plane wave type: diffracting vs Bloch\/periodic vs BFAST<\/p>\n
ii- plane wave frequency: CW vs short pulse envelope<\/p>\n
iii- boundary condition (Bloch vs periodic)<\/p>\n
iv- grating phase gradient using different lengths of the grating lines vs resonating patterns<\/p>\n
v- polarization<\/p>\n
vi- transmission and reflection <\/p>\n
2- calculating bandstructure and identification of forbidden transitions (final state located below the light line in the energy-momentum space)<\/p>\n
3- calculating coupling efficiency<\/p>\n
Appreciate your help.<\/p>\n","protected":false},"template":"","class_list":["post-361614","topic","type-topic","status-closed","hentry","topic-tag-3DFDTD-1","topic-tag-frequency","topic-tag-grating-1","topic-tag-plane-wave","topic-tag-plasmonics-1","topic-tag-spatial-variation"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t