26 research outputs found
Demonstration of whispering-gallery-mode resonant enhancement of optical forces
We experimentally studied whispering-gallery modes(WGMs) and demonstrated
resonance enhancement of optical forces evanescently exerted on dielectric
microspheres. We showed that the resonant light pressure can be used for
optical sorting of microparticles with extraordinary uniform resonant
properties that is unachievable by conventional sorting techniques.Comment: IEEE 2014 National Aerospace and Electronics Conference (NAECON),
Dayton, Ohio, June 201
Photodetector Focal Plane Arrays Integrated with Silicon Micropyramidal Structures in MWIR
Light-concentrating truncated Si micropyramidal arrays with 54.7 degree
sidewall angles were successfully integrated with PtSi Schottky barrier
photodetectors. Four different devices consisting of 10 x 10 photodetectors
with 60 um pitch combined in parallel were tested, where significant
enhancement capability was demonstrated by the Si micropyramids. The device
consisting of one hundred 22 um square detectors monolithically integrated with
the light-concentrating micropyramidal array displayed signal enhancement of up
to 4 times compared to the same size 22 um square photodetector device without
the light concentrators.Comment: 4 pages, 2 figures, GOMACTech 202
Focusing and Diffraction of Light by Periodic Si Micropyramidal Arrays
This research was devoted to modeling of the optical properties of Si
micropyramids aimed at designing optimal structures for applications as light
concentrators in mid-wave infrared (MWIR) focal place arrays (FPAs). It is
shown that completely different optical properties of such structures can be
realized using two types of boundary conditions (BCs): i) periodical and ii)
perfectly matched layer. The first type (periodical BC) allowed us to describe
the Talbot effect under plane wave coherent illumination conditions. This
effect was experimentally demonstrated in the proposed structures. The second
type (perfectly matched layer BC) allows describing the optical properties of
individual micropyramids concentrating or focusing light on the photodetector.
The optimal geometries of micropyramids required for maximizing the intensity
of photonic nanojets emerging from their truncated tips are determined.Comment: 4 pages, 5 figures, GOMACTech 202