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The spectrum of forward scattered radiation resulting from laser-induced air breakdown has been investigated using a single-mode ruby laser and a mode-locked neodymium: glass laser. The broadening observed provides additional evidence for self-focusing mechanism associated with the production of laser sparks.

Subpicosecond structure (3 × 10 -13 sec) has been observed in the output spikes of a Nd:glass laser by employing two photon fluorescence display inside the laser cavity. Contrast measurements are also reported.

We have studied the interaction between the 1010 W Nd glass laser pulses with a leading edge of about 1ns and several planar targets made of deuterium-contained materials. In our experiments, the neutron yields, electron temperature and various characteristics (such as reflectivity, temporal, spatial and spectral structure) of the backward-reflected laser light from the plasmas have been mainly measured.

(1982). High-Peak-Power Nd : Glass Laser Systems. Optica Acta: International Journal of Optics: Vol. 29, No. 1, pp. 5-5.

Kodak dye #26 was used to generate picosecond laser pulses by mode locking a Nd:glass laser. The intensity profiles and characteristics of the pulses were compared with those of pulses emitted using dyes # 5 and # 9860.

Nonlinear optical characteristics of transparent PLLZT ceramics have been examined. The ceramic samples have been prepared by various hot-pressing temperatures, pressures and soaking times, and optimum fabrication condition has been experimentally decided by the density, average grain diameter and optical transmittance measurements. An intense SHG light was observed for the first time on PLLZT ceramics when the ceramics were pumped by a Q-switched high repetition rate Nd3+ glass laser light. A conversion efficiency was about 0.17% at 13 MW pump power.

The 1979 Quantum Electronics Award of the IEEE Quantum Electronics and Applications Society will be presented to Dr. Elias Snitzer at the 1980 Conference on Laser and Electro-optical Systems in San Diego, CA, USA. Dr. Snitzer is cited for his invention and operation of the "first" glass laser, fiberoptics laser, and contributions to optical fibers. A brief review of Dr. Snitzer's career is provided.

The effects of pulsed ruby and Nd:Glass laser irradiation on the electrical properties of Si-mplanted GaAs were investigated to reveal the reason for the lack of activity in low-dose-implanted samples after pulsed-laser annealing. High electrical activity was observed in a sample implanted at a dose of 1015/cm2, while no activity was observed in a sample implanted at a dose of less than 1014/cm2 after the same pulsed laser annealing process. It was found that the ruby laser irradiation of a thermally-annealed sample greatly reduces the carrier concentration and mobility near the surface, while Nd: Glass laser irradiation does not. It is suggested that the surface melting and recrystallization that takes place at a high rate of cooling in pulsed annealing induces defects, giving rise to the lack of activity and low mobility in laser-annealed GaAs.

A frequency-doubled Nd:YAG/glass laser system has been constructed for use at the Combustion Research Facility at Sandia National Laboratories, Livermore. This laser system will be used to make single-shot spontaneous Raman spectroscopy measurements of ongoing combustion processes. The output of the system is 5 J of 1.064-microm radiation and 0.8 J of 532-nm radiation in a 2-microsec pulse. The repetition rate of the system is 1 pps. A microprocessor-based diagnostic and control system for the operation is described.

Using interferometric diagnostics by visible probing beam, we have studied the electron density profiles in coronal plasmas of solid targets irradiatied by Nd glass laser at an intensity of 1014 W/cm2. We have observed not only the phenomena such as density steepening and hollowing due to light pressure, but also different characters of density hollowing in various configuration targets.

Diffraction patterns caused by optical noise sources have severe detrimental effects on high power glass laser systems. We have experimentally and analytically studied the diffraction patterns caused by phase perturbation as well as by intensity perturbation and have obtained them at various locations before and after spatial filtering. Based on these results, the maximum size of noise sources that are allowable in glass laser systems have been determined.

This paper discusses three articles that deal with the detailed target physics phenomena and the underlying science of driver development. The articles provide perspective for future articles on reactor implications and program plans. Specifically, the articles deal with the target requirements for a laser fusion reactor with consideration of the direct illumination approach, the issue of ion beam propagation and focusing, and high power laser for fusion applications including the Nova glass laser and Antares CO/sub 2/ laser now under construction.

In this paper, influence of the terminal level lifetime on Nd-glass laser amplifiers has been investigated by using a computer. Results show that, for a Nd-glass laser amplifier with dimension of φ20×480 mm, when the Nd-glass terminal level lifetime is decreased from 100 ns to 1 ns, the influences on an input pulse with a 20 ns width and 2.0 J/cm2 energy density are as follows: the gain increases by～20%; the distortion of the pulse peak decreases by～20%; and the amplifier's saturation length decreases by～30%.

This paper reports a nuclear analysis of the neutrons from a DT pellet measured in inertial confinement fusion experiments in the GEKKO XII glass laser system. The items discussed are the neutron energy spectrum from a pellet and the outside of the chamber wall, the neutron leakage fraction through the wall and the windows of the chamber, the induced radioactivity of the activation test pieces, and the effects of these on the neutron measurements. The dose due to the fusion neutrons and γ-rays and the induced radioactivity is also described.

Regarding the section on conversion efficiency on p. 1474 [Sec. II, part (5)], the reference to Eq. (2) in the text is in error and should in fact read, ‘‘Equation (1) provides...’’ Also, in Fig. 3 the reference to Eq. (2) should be a reference to Eq. (1). Finally, in Fig. 3, the reference to Eq. (3) in fact refers to the unnumbered expression for PDCE’ in the text on p. 1474, column 2.

Rodney Hodgson of IBM Research has built the shortest‐wavelength laser ever made, making hydrogen lase in the vacuum ultraviolet on eighteen lines between 1520 and 1615 A, corresponding to photon energies of about 8 eV. Previously the shortest wavelength was 2120 A, obtained by frequency multiplication of 10 600‐A light from a neodymium‐doped glass laser. The new vacuum uv laser is expected to be useful in the study of chemical reactions and the interaction of high‐energy photons with matter.

THE generation of high-peak power pulses of short duration from a ruby laser by the incorporation of a reversible bleachable absorber into the optical cavity has recently been reported1. This communication reports the observation of giant pulses at 1.06µ from a neodymium glass laser using the polymethine dye 3,3′-diethyl-9,11; 15,17-dineopentylene-thia-pentacarbocyanine iodide2 as the bleachable absorber.

Fast pulses from a Nd: glass laser (10 600 A), with a rise time of 0.7 nsec and a length of 1.3 nsec at half‐intensity interact with mercury atoms via the 73S1 − 73P2 transition (11 287 A). The 73S1 level shifts instantaneously to higher energies by 0.29 × 10−6 eV for a laser power of 1 MW/cm2. Theoretical behavior of the 73S1 level is given. The absorption oscillator strength of the 73S1 − 73P2 transition is deduced to be 0.32±0.06.

It is found that laser emission can be obtained in narrow lines less than 0.1 A wide anywhere within a 130-A interval centered about the peak emission at 1.06 mu by the use of thin reflecting plates acting as wavelength-sensitive mode selectors. For a plate aligned perpendicular to the axis of the laser the emission is at those wavelengths at which the plate thickness is an odd number of quarter wavelengths. The plate tends to produce a spiking emission as a function of time and no loss in output energy.

THE homopolar generator1,2 at the Australian National University in Canberra can be connected to deliver 1.5 × 106 A at more than 800 V for 0.1 s. When light sources capable of handling such power and energy are developed, it will be possible to use the energy to pump a large laser. We have used the generator with its four disks in series to power a co-axial discharge tube filled with xenon at a pressure of 30 cm of mercury. During a pulse lasting for 7.5 ms we injected 6,000 J/inch into the flash tube which enclosed a Nd glass laser rod 0.5 inches in diameter and 6 inches long. The fluorescent lifetime of the glass is quoted as 360 µs. A record of the radiation intensity is shown in Fig. 1. The decrease in intensity with time was caused by the current being reduced by a variable resistor in series with the lamp, increasing in preparation for the termination of the pulse. If the laser assembly could stand it, a pulse of this power could be supplied for 50 s from the generator.