A wavelength-swept thulium-doped fiber laser system employing two parallel cavities with two different fiber gain stages is reported. The fiber gain stages were tailored to provide emission in complementary bands with external wavelength-dependent feedback cavities sharing a common rotating polygon mirror for wavelength scanning. The wavelength-swept laser outputs from the fiber gain elements w...

Very low energy scanning electron microscopy is introduced as a scanning version of the low energy electron microscopy, i.e. the emission electron microscopy with the sample excited by means of a parallel wave of electrons. The incident primary electrons are retarded in the cathode lens consisting of a negatively biased sample (cathode) and earthed anode. Interaction of slow electrons with soli...

Nanoporous silicon powder was produced via efficient magnesiothermic reduction. In this work, the thermal effect and reduction process time were investigated on the porous silicon structure. The nanoporous silicon powders were characterized by  X-ray diffraction analysis and field emission scanning electron microscopy. The results demonstrate that porous structure was changed to homogeneous and...

The light emission from a scanning tunneling microscope operated on a Ag(111) surface at 6 K is analyzed from low conductances to values approaching the conductance quantum. Optical spectra recorded at sample voltages V reveal emission with photon energies hν>2eV. A model of electrons interacting coherently via a localized plasmon-polariton mode reproduces the experimental data, in particular, ...

INTRODUCTION Fluorodeoxyglucose positron emission tomography scanning has an established role in the diagnostic work-up of many malignant diseases and also in the evaluation of cancer treatment response. Fluorodeoxyglucose positron emission tomography may, however be non-specific as infectious processes are depicted as well. CASE PRESENTATION We present a patient with longstanding leg pain an...

This study has investigated the effect of dopant concentration on the luminescent emission of Er in ZrO2 nanocrystals. The structure and morphology of the resulting nanocrystals were characterized by X-ray diffraction and field emission scanning electron microscope. The room-temperature optical properties of synthesized nanocrystals were studied by photoluminescence spectroscopy. The dependence...

The photoluminescence emission of nanoporous anodic aluminum oxide films formed in phosphoric acid is studied in order to explore their defect-based subband electronic structure. Different excitation wavelengths are used to identify most of the details of the subband states. The films are produced under different anodizing conditions to optimize their emission in the visible range. Scanning ele...

Using a nanomanipulation system contained within a scanning electron microscope we investigate the thermionic electron emission from multiwall carbon nanotubes. Peak emission currents of 65 nA are measured. The carbon nanotubes being grown at low temperature by the chemical vapor deposition method are defective with poor thermal conductivity. We believe it is crucial for the thermal conductivit...

We use electric field singularities in biased metal semiconductor microstructures to enhance the generation of terahertz (THz) radiation from semiconductors. We find that, regardless of the mechanism that is responsible for enhanced THz emission near the anode, singular electric fields near sharp anode features will enhance this emission by as much as an order of magnitude. We show scanning THz...

This study describes a scanning time-resolved fluorescence spectroscopy (TRFS) system designed to continuously acquire fluorescence emission and to reconstruct fluorescence lifetime images (FLIM) from a luminal surface by using a catheter-based optical probe with rotary joint and pull-back device. The ability of the system to temporally and spectrally resolve the fluorescence emission from tiss...