P. Pagliusi, G. Cipparrone
Jan 8, 2002
Citations
1
Influential Citations
59
Citations
Journal
Applied Physics Letters
Abstract
We report a study of diffraction gratings observed in planar cells of nematic mixture (cyanobiphenyl and cyanotriphenyl derivatives, E7) made with different aligning substrates. Under the combined application of very low intensity laser beams (1.8 mW/cm2) and low dc voltage (4 V), highly sensitive gratings have been observed in degenerate four-wave-mixing experiments. Beam coupling measurements confirm the photorefractive-like nature of the gratings. Interesting results are obtained using two different liquid crystals, depending on the aligning substrates. The observed behavior suggests the fundamental role of the interfaces in the photoinduced processes.