Size-dependent trapping behavior and optical emission study of NaYF4 nanorods in optical fiber tip tweezers.

Trapping of NaYF:Er/Yb/Gd nanorods using an original optical fiber-tip tweezers is reported. Depending on their length, nanorods are reproducibly trapped in single or dual fiber tip configurations. Short rods of 600 nm length are trapped with two fiber tips facing each other.

Luminescent nanoparticle trapping with far-field optical fiber-tip tweezers.

We report stable and reproducible trapping of luminescent dielectric YAG:Ce(3+) nanoparticles with sizes down to 60 nm using far-field dual fiber tip optical tweezers. The particles are synthesized by a specific glycothermal route followed by an original protected annealing step, resulting in significantly enhanced photostability. The tweezers properties are analyzed by studying the trapped particles residual Brownian motion using video or reflected signal records.

Optical binding of cylinder photonic molecules in the near field of partially coherent fluctuating Gaussian Schell model sources: a coherent mode representation.

We present a theory and computation method of radiation pressure from partially coherent light by establishing a coherent mode representation of the radiation forces. This is illustrated with the near field emitted from a Gaussian Schell model source, mechanically acting on a single cylinder with magnetodielectric behavior, or on a photonic molecule constituted by a pair of such cylinders. Thus after studying the force produced by a single particle, we address the effects of the spatial coherence on the bonding and antibonding states of two particles.

Optical forces on cylinders near subwavelength slits: effects of extraordinary transmission and excitation of Mie resonances.

We study the optical forces on particles, either dielectric or metallic, in or out their Mie resonances, near a subwavelength slit in extraordinary transmission regime. Calculations are two-dimensional, so that those particles are infinite cylinders. Illumination is with p-polarization.

Enhanced transmission through subwavelength apertures by excitation of particle localized plasmons and nanojets.

We study, and illustrate with numerical calculations, transmission enhancement by subwavelength 2D slits due to the dominant role played by the excitation of the eigenmodes of plasmonic cylinders when they are placed at the aperture entrance; and also due to reinforced and highly localized energy in the slit as a consequence of the formation of a nanojet. We show that, providing the illumination is chosen such that an aperture transmitting eigenmode is generated, the phenomenon is independent of whether or not the slit alone produces extraordinary transmission; although in the former case this enhancement will add to this slit supertransmission. We address several particle sizes, and emphasize the universality of this phenomenon with different materials.