This letter reports on the growth, structure, and luminescent properties of individual multiple quantum well (MQW) AlGaAs nanowires (NWs). The composition modulations (MQWs) are obtained by alternating the elemental flux of Al and Ga during the molecular beam epitaxy growth of the AlGaAs wire on GaAs (111)B substrates. Transmission electron microscopy and energy dispersive X-ray spectroscopy pe...

This work presents a detailed investigation of electromagnetic coupling to the surface plasmon-polariton ~SPP! at microwave frequencies. We have recorded the wavelength-dependent reflectivity from a metallic sinusoidal diffraction grating of pitch 15 mm. In order to minimize the problems associated with nonplanar incident wavefronts, we have developed an apparatus that collimates the incident b...

The manipulation of a Gaussian laser beam using conical diffraction in a high optical quality biaxial crystal of KGd(WO(4))(2) has been examined in detail with emphasis on the experimental techniques involved and intuitive explanations of the notable features. Two different optical arrangements were used to form the Pogendorff double-ring light pattern in the focal image plane. The formation of...

It is shown that a very simple model reproduces the pressure versus beam current characteristics of elongated single-cavity boiling water targets for F production surprisingly well. By fitting the model calculations to measured data, values for a single free parameter, namely an overall heattransfer coefficient, have been extracted for several IBA Nirta H2 O targets. IBA recently released detai...

We report experiments on self-focusing of femtosecond diffraction-resistant vortex beams in water. These beams are higher-order Bessel beams with weak azimuthal modulation of the transverse intensity patterns. The modulation overrides the self-focusing dynamics and results in the formation of regular bottlelike filament distributions. The peak-power thresholds for filamentation, at a particular...

the root pulling force as well as the amount of transferred soil have not been reported quantitatively for various sugar beet types. this study was designed to measure the amounts of transferred soil from farm and estimate the root pulling force among sugar beets populations with different root shapes at harvest time. the experiment was conducted as a split plot with a randomized complete block...

Type I and type II second harmonic generation (SHG) of a beam transformed by the conical refraction phenomenon are presented. We show that, for type I, the second harmonic intensity pattern is a light ring with a point of null intensity while, for type II, the light ring possesses two dark regions. Taking into account the different two-photon processes involved in SHG, we have derived analytica...

We report simultaneous generation of multiple conical second-harmonic waves in a two-dimensional nonlinear photonic structure when illuminated by two overlapping noncollinear fundamental beams. We show that this phenomenon is caused by the nonlinear Čerenkov radiation emitted due to the interaction of photons from each constituent fundamental beam as well as the virtual one propagating along th...

We construct near-infrared to visible broad band NICMOS/WFPC color maps for 4 early-type Seyfert galaxies with S-shaped or one-sided ionization cones. We find that dust lanes are near or connected to many of the features seen in the [OIII] and Hα+[NII] line emission maps. This suggests that much of the structure of line emission in these ionization cones is determined by the distribution of amb...

BACKGROUND This paper describes the shaping of freestanding objects out of metallic structures in the nano- and submicron size. The technique used, called nanoforging, is very similar to the macroscopic forging process. RESULTS With spring actuated tools produced by focused ion beam milling, controlled forging is demonstrated. With only three steps, a conical bar stock is transformed to a fla...