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M Megens

Publications and source records attributed to M Megens.

2 recordsLinked to original sources
PubMed2002

Electro-optic response and switchable Bragg diffraction for liquid crystals in colloid-templated materials.

We report optical switching studies on nematic liquid crystal incorporated into structures based on self-assembled colloids. We compare the electro-optic responses of liquid crystal imbibed into colloid-templated polymers, liquid crystal imbibed in the interstitial space of colloid crystals, and conventional polymer-dispersed liquid crystals. We characterize the Bragg diffraction of our templated liquid-crystal/polymer composites as a function of electric field and measure switching times. The response of liquid crystal in connected networks differs qualitatively from that of liquid crystal in isolated cavities.

Journal Article↗
PubMed2001

Particle excursions in colloidal crystals.

We have performed synchrotron small-angle x-ray diffraction experiments on charge-stabilized colloidal crystals. The mean squared displacements, obtained from Debye-Waller factors, decrease with increasing density beyond freezing. Irrespective of the range of the repulsion, our data and previous results lie on a common curve, linearly scaled between the melting and close-packed densities. Surprisingly, the excursions are smaller than predicted by theory.

Journal Article↗