[7p-S44-1~18] 3.1 Basic optics and frontier of optics

[7p-S44-16] Optical trapping of individual dye-doped polystyrene particles with resonant laser near absorption peak

〇Tetsuhiro Kudo¹, Hajime Ishihara^2,3, Hiroshi Masuhara¹ (1.National Chiao Tung Univ., Taiwan, 2.Osaka Pref. Univ., 3.Osaka Univ.)

Keywords:Optical trapping, Resonance effect, Polystyrene particles

We demonstrate resonance optical trapping of individual dye-doped polystyrene particles with blue- and red-detuned lasers whose energy are higher and lower compared to electronic transition of the dye molecules, respectively. Through the measurement on how long individual particles are immobilized at the focus, we show that immobilization time of dye-doped particles becomes longer than that of bare ones. Further, we directly confirm that the immobilization time of dye-doped particles trapped by the blue-detuned laser becomes longer than that by the red-detuned one. These results are well interpreted by our theoretical proposal based on nonlinear optical response under intense laser field. Our finding reveals the novel aspect that particles’ behavior in irradiated area is directly affected by nonlinear interaction of light and matter through the optical force.