November 21, 2014 - 3:00pm - 4:00pm
Novel combinations of photosensitive materials and electro-optic fluids open
up the coupling of stimuli-driven modulation of the optical properties of
liquid crystal/polymer material systems. We explore a new generation of
polymer-dispersed liquid crystals (LCPDLCs) that exhibit excellent optical and
electro-optical properties with negligible scattering losses in both ON and
OFF states enabled by proper design of the reactive mesogenic monomer.
Polarized optical microscopy and environmental scanning electron microscopy
reveal a regular and uniform morphology made of well oriented polymeric
stripes without the evidence of micro-sized nematic liquid crystals droplets.
This talk will also focus on novel periodic structures formed through a
combination of photosensitive liquid crystals, photosensitive LC monomers, and
photosensitive surfaces to modulate the amplitude of the refractive index
profile through the thickness of a cell while being able to pattern
information in the x-y plane. These films are formed through
polymerization-driven processes induced using holography. Light induced
planar to twist reorientation of LC/plasmonic cells incorporating gold nanorods is
demonstrated. This produces a localized refractive index variation in the
environment around the GNRs, affecting the position of the plasmonic
resonance, yielding a shift of about 100 nm. Active control of the LPR of
GNRs represents a crucial step toward the realization of active photonic
devices based on plasmonic nanomaterials.