Optical manipulation with nanostructures
le 27 juin 2016 à 11 h
Ivan Gusachenko, Light-Matter Interaction Unit, OIST, Okinawa, Japan and Optical Manipulation Group, School of Physics and Astronomy, University of St Andrews, Scotland
Lieu(x) : Amphithéatre Sauvy, Ecole Polytechnique
Contact : Marie-Claire Schanne-Klein
marie-claire.schanne-klein at polytechnique.edu
Since the demonstration of optical tweezers in 1986 by Ashkin there have been significant efforts to achieve trapping and manipulation of nanoscale objects, and a variety of geometries and properties of the optical field has been explored for this purpose. I will talk about two nanostructres studied for optical manipulation in Light-Matter Interaction unit in Okinawa Institute of Science and Technology: optical nanofibers and metal nanoapertures.
A special case of evanescent field geometry is found in the optical nanofiber. With a diameter smaller than the wavelength of the light guided within, such ultrathin optical fibers have intense evanescent fields, which penetrate into the surrounding medium. Such a system represents a unique framework for optical manipulation with extreme aspect ratios, suitable for sorting applications.
Another geometry relies on the field confinement exerted by metal nanostructures, which has been shown efficient for achieving nanometer-scale traps with moderate optical powers. In this part of my talk I’ll describe metal nanoapertures outside of the plasmon resonance, which additionally take advantage of the self-induced back action principle enhancing trapping efficiency.
À télécharger : Seminaire GUSACHENKO.PDF