Reconfiguring Nanocomposite Liquid Crystal Polymer Films with Visible Light

Patterns of white light are projected
on liquid crystal (LC) polymer
films containing gold nanospheres (NS) or nanorods (NR) to induce
out-of-plane buckling through a photothermal effect. Straightforward
synthetic techniques are used to provide well-dispersed nanocomposite
films, with NRs exhibiting self-alignment with the LC director. Using
a combination of prepatterned director orientation and spatiotemporal
variations in light intensity, these nanocomposite films can be reversibly
configured into different 3D states. Fine control over shape is demonstrated
through variations in size, shape, and intensity of the illuminated
region. Switching time scales are found to be of order a few seconds
or below, likely reflecting the intrinsic relaxation time of the LC
materials.