Simultaneous Imaging and Selective Photothermal Therapy through Aptamer-Driven Au Nanosphere Clustering.

Gold (Au) nanoparticles display enhanced near-infrared (NIR) photothermal effects upon the formation of clusters. We studied the photothermal properties of Au nanosphere clusters on the single-particle level using photothermal heterodyne imaging (PTHI) microscopy to understand the enhancement mechanisms. NIR photothermal responses of Au nanoparticle clusters were found to significantly increase from monomers to trimers.

Single-Particle Spectroscopic Study on Fluorescence Enhancement by Plasmon Coupled Gold Nanorod Dimers Assembled on DNA Origami.

Metal-enhanced fluorescence has attracted much attention due to its scientific importance and lots of potential applications. Plasmon coupled metal nanoparticles have been demonstrated to further improve the enhancement effects. Conventional studies of metal-enhanced fluorescence on the bulk systems are complicated by the ensemble average effects over many critical factors with large variations.

Gold nanorod enhanced two-photon excitation fluorescence of photosensitizers for two-photon imaging and photodynamic therapy.

Plasmon enhancement of optical properties is both fundamentally important and appealing for many biological and photonic applications. Although metal-enhanced two-photon excitation fluorescence has been demonstrated in the solid substrates, there is no report on metal enhanced overall two-photon excitation fluorescence in the colloid system. Here we systematically investigated gold nanorod enhanced one- and two-photon excitation fluorescence of a porphyrin molecule, T790.

Photonic crystal fiber tip interferometer for refractive index sensing.

In this paper we present an interferometer based on photonic crystal fiber (PCF) tip ended with a solid silica-sphere for refractive index sensing. The sensor is fabricated by splicing one end of the holey PCF to a single mode fiber (SMF) and applying arc at the other end to form a solid sphere. The sensor has been experimentally tested for refractive index and temperature sensing by monitoring its wavelength shift.

High-energy laser pulse with a submegahertz repetition rate from a passively mode-locked fiber laser.

We demonstrate an ultralong cavity, all-fiber, all-normal-dispersion Yb-doped fiber laser that is passively mode locked by a semiconductor saturable absorber mirror (SESAM). Without any discrete dispersion-compensation components or conventional spectral filters, the SESAM works together with the strongly chirped pulse and the nonlinearity induced spectrum broadening to perform a filtering-equivalent function, thus stabilizing the mode locking. The laser generates 4.