The 67th JSAP Spring Meeting 2020

Presentation information

Oral presentation

3 Optics and Photonics » 3.11 Photonic structures and phenomena

[14p-B415-1~15] 3.11 Photonic structures and phenomena

Sat. Mar 14, 2020 1:30 PM - 5:50 PM B415 (2-415)

Kenji Ishizaki(Kyoto Univ.), Satoshi Iwamoto(Univ. of Tokyo), Akihiko Shinya(NTT)

3:50 PM - 4:05 PM

[14p-B415-9] Enhancing Radiation Force at Solution Interface: the Role of Optical Resonance Effect

〇(P)Roger Bresoli1, Boris Louis1,2, Tetsuhiro Kudo3, Hiroshi Masuhara3,4, Johan Hofkens1 (1.KU Leuven, 2.Lund Univ., 3.NCTU, 4.CEFMS NCTU)

Keywords:Optical trapping, Interface, Resonance effect

In 1986, Prof. Ashkin and coworkers demonstrated that a tightly focused laser beam inside solution could be used to trap particles at the focal spot 3D, when the gradient force is larger than scattering and absorption forces. The radiation force is a function of induced polarization and spatial gradient of the laser, and considerable amounts of the studies have been carried out for many nanomaterials with various laser light over multidisciplinary research fields.
Herein, we demonstrate the effect of widefield inlumination (488 nm) on the trapping behavior of dye-doped polystyrene beads (continuous wave, 1064 nm wavelength laser) at glass/solution interface. Using a multiplane widefield microscope, we have been capable to study the motion of such trapped beads in 3D and the trapping stiffness is estimated. Finally, to our best knowledge the optical resonance effect has never been studied at the interface and there we observed that scattering and absorption forces may also play a role in the particle trapping.