|
Zooming in with AFM on a Photonic Band Gap Structure
Photonic Band Gap materials or PBGs are important optical device structures for which NSOM is a critical characterizing tool .
| (Left) 20x20um AFM image of the PBG crystal. Tapping mode with 40kHz resonance frequency.The boxed region is imaged to the right in an 8x8um scan. |
| (Middle) 8x8 um AFM image of the boxed region in the 20 x 20um scan (left). |
| (Right) 3.1x3.1um image of the boxed region in the 8x8um image to the left. |
PBG Topography Correlated with Light Concentration In this PBG gaps develop between domains.
 |
 |
| AFM topographic image of such a gap with a depth of ~3um. |
NSOM collection mode image of the same region with PBG illuminated from the bottom with a UV lamp.
|
 |
Collage 3D image of AFM topography and NSOM light distribution. As is clearly seen the light is concentrated in the gap & clings preferentially to the walls.
|
NSOM Collection Mode of Guided Light in a PBG
Green light in a domain (bright triangular region left) propagates in a gap that develops between two dark domains seen emanating from the triangular domain.
|
