Document DOI: 10.1209/epl/i2002-00403-3
Europhys. Lett., 58 (5) , pp. 679-685 (2002)
Switchable Bragg diffraction from liquid crystal in colloid-templated structures
P. Mach1, 2, P. Wiltzius2, M. Megens2, D. A. Weitz3, Keng-hui Lin1, T. C. Lubensky1 and A. G. Yodh11 Department of Physics and Astronomy, University of Pennsylvania Philadelphia, PA 19104-6396, USA
2 Bell Laboratories, Lucent Technologies - Murray Hill, NJ 07974, USA
3 Physics Department and DEAS, Harvard University - Cambridge, MA 02138, USA
(Received 3 December 2001; accepted in final form 6 March 2002)
Abstract
We have incorporated nematic liquid crystal into periodic,
polymer host structures templated from self-assembled colloids.
Using these composite materials, we demonstrate the first
electrically switchable three-dimensional Bragg diffraction. The
switchable beam deflection is potentially useful for
non-mechanical beam steering and optical beam splitting devices.
We compare the electro-optic response of our templated
liquid-crystal/polymer composites with conventional
polymer-dispersed liquid crystals (PDLCs). Our data reveal a
qualitatively different and faster response for liquid crystal
distributed within a connected cavity network, as compared to
isolated liquid-crystal droplets within a polymer matrix.
47.20.Dr - Surface-tension-driven instability.
61.30.Pq - Microconfined liquid crystals: droplets, cylinders, randomly confined liquid crystals, polymer dispersed liquid crystals, and porous systems.
82.70.Dd - Colloids.
© EDP Sciences 2002