Delayed onset of photochromism in molybdenum oxide films caused by photoinduced defect formation.

We report the photochromic properties of amorphous MoO films deposited by dc sputtering with different O flow rates. The kinetics of film coloration under UV light irradiation is determined using optical transmission spectroscopy. Changes in the absorbance and refractive index were derived from the analysis of transmittance spectra.

Distortion of terahertz signals due to imperfect synchronization with chirped probe pulses.

Terahertz (THz) signals measured by means of the spectral-encoding technique with different temporal discrepancies between probe pulses and THz signals are investigated. It is found that imperfect synchronization between the chirped probe and THz pulses induce a distortion and this distortion affects significantly the retrieved THz spectrum if the temporal discrepancy is large. The distortion becomes more prominent if the probe pulse length is less than the optimal chirped probe pulse duration.

Wide-field single metal nanoparticle spectroscopy for high throughput localized surface plasmon resonance sensing.

Noble metal nanoparticles (mNPs) have a distinct extinction spectrum arising from their ability to support Localized Surface Plasmon Resonance (LSPR). Single-particle biosensing with LSPR is label free and offers a number of advantages, including single molecular sensitivity, multiplex detection, and in vivo quantification of chemical species etc. In this article, we introduce Single-particle LSPR Imaging (SLI), a wide-field spectral imaging method for high throughput LSPR biosensing.

Dynamical observation of bamboo-like carbon nanotube growth.

The growth dynamics of bamboo-like multiwalled carbon nanotubes (BCNTs) via catalytic decomposition of C2H2 on Ni catalyst at 650 degrees C was observed in real time using an in situ ultrahigh vacuum transmission electron microscope. During BCNT growth, the shape of the catalyst particle changes constantly but remains metallic and crystalline. Graphene sheets (bamboo knots) within the nanotube preferentially nucleate on the multistep Ni-graphite edges at the point where the graphene joins the catalyst particle, where it is stabilized by both the graphene walls and the Ni catalyst surface.

Direct observation of single-walled carbon nanotube growth at the atomistic scale.

The growth dynamics of a single-walled carbon nanotube (SWNT) is observed in real-time using an in situ ultrahigh vacuum transmission electron microscope at 650 degrees C. SWNTs preferentially grow on smaller sized catalyst particles (diameter View Article and Find Full Text PDF