Effect of Nonlinear Optical Reorientation on Optical Trapping in Nematic Liquid Crystals
Liana Lucchetti, Luigino Criante, Francesco Bracalente, Francesco Aieta and Francesco Simoni
We report the results of an investigation of optical trapping in liquid crystals under forbidden conditions, that is when the refractive index of the particle to be trapped is smaller than the one of the surrounding medium. To this aim an optical tweezers apparatus has been equipped with a second weak laser beam acting as a probe of the optical reorientation of liquid crystal molecules. We demonstrate the strong relationship between the nonlinear optical properties of nematic liquid crystals and the strength of the trapping forces.
Keywords: optical trapping; nematic liquid crystals
PACS codes: 87.80.Cc Optical Trapping; 42.70.Df Liquid Crystals