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Updated: Jul 13, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Lattice dynamics of two-dimensional colloidal crystals subject to external light potentials
H H von Grünberg1, J Baumgartl
1Institut für Chemie, Karl-Franzens-Universität, Graz, Austria.
Abstract:
By exposing two-dimensional crystals to tunable substrate potentials one can selectively manipulate the crystal's phonon band structure. We explore this idea and study the overdamped lattice dynamics of colloidal crystals subject to commensurate substrate potentials with sinusoidal modulations in up to two spatial directions. We furthermore show that the mean-square displacement of colloids in the crystal can be understood as the Laplace transform of the phonon spectrum and discuss how our results can best be verified experimentally.
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