Optical control of surface anchoring and reorientation of liquid crystals via a plasmon-enhanced local field.
Gold nanoparticles deposited on the windows of a liquid crystal (LC) cell were found to be able to reduce the surface anchoring energy of the LC, and hence the threshold for its reorientation phase transition, by 1 to 2 orders of magnitude when a cw pump light was used to excite the local plasmon resonance of the nanoparticles. The effect was due to the disorientation of LC molecules between nanoparticles by the plasmon-enhanced local field that softens the effective surface anchoring. A light-controlled variation of surface anchoring energy could provide new opportunities for optoelectronic applications of a LC.
Key Lab for Micro and Nanophotonic Structures (Ministry of Education), Department of Optical Science and Engineering, School of Information Science and Engineering, Fudan University, Shanghai 200433, China.
J
J
Shan
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W
Shi
L Y
LY
Liu
Y R
YR
Shen
L
L
Xu