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A vacuum-ultraviolet photoabsorption imaging method was used, based on time and space resolved absorption of quasimonochromatic VUV beams from laser plasma.

A new study investigates the time-resolved dielectric and photoabsorbance properties of a nematic eutectic mixture doped with a photoactive azo mesogen at room temperature.

Research was conducted to examine the X-ray photoemission and photoabsorption of tris(8, hydroxyquinoline) aluminum, an organic electroluminescent material. The electronic properties and damage mechanisms of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD) were also studied. It was shown that valence band and core level photoelectron spectroscopy and absorption spectroscopy are well-suited to examine the element-specific structure of organic molecules used in organic light-emitting devices.

The ultraviolet-photon absorption constants for thin CsI, KI, RbI, NaI and CsBr evaporated films were obtained in the 140-200 nm range. The constant calculated for CsI was in agreement with previous reports while the absorption data for the other materials were determined for the first time. Post-evaporation thermal treatment of the films, which is believed to improve the photoemission behavior of CsI, NaI and CsBr films, had no impact on their photoabsorption characteristics.

Temporally- and spatially-resolved absorption and emission spectra were measured at various detection angles to examine NiO laser ablation at 266 nm. Ground states, excited states, lower lying states and other electronic states were differentiated from emission and absorption spectroscopy. Results show that excited Ni neutrals are produced mainly by the recombination of electrons and Ni+ ions.

Surface photoabsorption was employed in the in situ measurement of surface structure transient in heterostructures prepared by altering P precursor partial pressure. The surface photoabsorption transient was correlated with heterostructure abruptness. The inclusion of a pause between the two layers following the flow rate reduction of the P precursors phosphine was found to minimize the magnitude of the memory effect.

Optical absorption and photoluminescence studies were conducted on low pressure metal-organic vapor phase epitaxy-grown strained-layer InAsxP1-x/InP(001)(x

An experiment was undertaken to study the reliance of the negative nonlinear absorption (NNA) effect on modulation frequency and degree, sample temperature and erbium concentration present in the erbium yttrium aluminum garnet crystal. The NNA effect was dependent on both the wavelength of the incident laser and sample length and that the process of improved absorption was similar to a four-level laser system. It was asserted that the NNA effect was described by calculating the rate equations based on an analytical model for a five-level system of the erbium ion.

The monolayer growth of gallium arsenide at 650 degrees Celsius by metalorganic chemical vapor deposition was monitored using surface photoabsorption. Scanning photoluminescence measurements of the surfaces were performed to investigate the accuracy of the growth control. Results showed that the observed spectra and model computations in both line width and peak energies were highly compatible.

A study was conducted on GexSi1-x/Si heterojunction internal photoemission detectors with medium- and long-wave infrared regions. Photoresponse measurements were compatible with a theory which considers excited carrier scattering. Results show that at 40 K, heterojunction internal photoemission detectors are capable of background-limited operation in long-wave infrared regions.

Absorption in two types of long-wave infrared detector structures prepared through ultrahigh vacuum chemical vapor deposition was measured. The heterojunction internal photoemission and multiple quantum well structures exhibited dominant free-carrier absorption for normally incident radiation. Resulting absorption values were found in agreement with the classical expression for free-carrier absorption.

The Monte Carlo simulation model was used to investigate the distributions of the number of primary electrons produced per incident mono-energetic x-rays in the 1- to 41-keV energy range comprising the xenon L- and K-absorption edges. The results of the simulation results were compared with recent data and experimental values measured with a gas proportional scintillation counter. Findings indicate a discontinuous behavior with incident x-ray energy which results in an ambiguity in the determination of the x-ray energy in certain narrow ranges containing the edges.

The reverse mirage or photothermal beam deflection (PBD) effect is simulated via a mathematical model and the results of the simulations are compared with experimental PBD data. The model is based on a one-dimensional thermal wave approach and simulates PBD with the laser probe on the nonilluminated side of the absorbing medium. A theoretical background on the model is presented. Meanwhile, experimental PBD data are obtained via a step-scan Fourier transform infrared PBD measurements. Details of the experiment, particularly the construction of a beam deflection accessory and a sample cell, are described and illustrated. Results of the PBD experiments are also given.

A study was conducted on the temperature dependence of the CuIn3Se5 fundamental absorption edge. A model developed by RJ Elliot offers an explanation to the optical absorption coefficient variation with fundamental edge energy at various temperatures. The resulting temperature dependence was found to be in agreement with a semiempirical model developed by A Manoogian and JC Wolley.