摘要:

The output energy from a uv preionized discharge excited XeFC→Alaser has been increased two orders of magnitude by injecting a dye laser pulse into theC→Aoscillator cavity. Output energies greater than 4 mJ with a spectral bandwidth of approximately 3 nm have been measured. By tuning the injected dye laser pulse, the output from theC→Alaser was tuned from 460 to 515 nm.

ISSN:0003-6951    

DOI:10.1063/1.91016

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

This study was undertaken in order to determine whether the observed premature 172‐nm laser pulse termination in pure xenon was caused by medium absorption. The absorption was measured by probing thee‐beam excited xenon with an ArF (193 nm) laser. Analysis of the results indicates that premature pulse termination cannot be explained entirely by the observed medium absorption.

ISSN:0003-6951    

DOI:10.1063/1.91017

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

We demonstrate that half‐wavelength facet coatings of Al2O3can arrest the growth of pulsations in the output intensity of (Al,Ga)As double‐heterostructure lasers during cw aging in a 70 °C dry nitrogen ambient while also eliminating an initial mode of degradation. These concurrent effects of the coatings suggest a common origin for the aging‐induced pulsations and the initial degradation and also support a recently proposed model for the origins of pulsations.

ISSN:0003-6951    

DOI:10.1063/1.91018

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A new hybrid far infrared (FIR) laser is described. The output beam has the form of the fundamental Gaussian mode. The radiation is pulsed due to passiveQswitching by the FIR laser gas CH3F. This type of resonator is expected to combine excellent FIR beam geometry, stability, and efficiency.

ISSN:0003-6951    

DOI:10.1063/1.91019

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Planar‐channeled electrons radiate electromagnetic energy with sharp peaks in the emission spectrum. A model is developed to predict the locations of these peaks, which are shown to correlate well with experimental observations. A by‐product of the model is that it provides a sensitive method for determining the interplanar potential energy function in a crystal.

ISSN:0003-6951    

DOI:10.1063/1.91020

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A UV preionized, high‐purity construction, closed‐cycle‐flow rare‐gas‐halide laser has been constructed to study laser characteristics at high pulse repetition frequency and closed cycle behavior of the laser chemistry. Operating characteristics of the laser with ArF, KrF, XeF, and XeCl have been obtained. The XeCl laser has demonstrated the best performance, yielding a maximum average power of 45 W at 600 Hz and greater than 35 W at 500 Hz for 1 h.

ISSN:0003-6951    

DOI:10.1063/1.91021

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

In a conventional circular cross‐section single‐mode fiber, built‐in and induced birefringences remove the degeneracy and make the fiber a two‐Eigenmode system. We have constructed the first all‐fiber interferometric sensor system and have performed preliminary studies on the effects of birefringence in these interferometers. Theoretical analysis and experimental data supporting this analysis are presented for the 3‐dB coupler and all‐fiber interferometer sensor.

ISSN:0003-6951    

DOI:10.1063/1.91022

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Calculations are reported of the contributions of the lowest2&Sgr;+uand2&Sgr;+gresonant states to the rates of dissociative attachment of electrons to H2and D2. For all electron temperatures, the rate is significantly enhanced by vibrational and rotational excitation of the initial molecule. Typically, for an electron temperature of 1.5 eV, the attachment rates for various (v,J) levels are, in cm3 sec−1, 5.4×10−15for (0,0), 7.2×10−11for (0,20), and 7.8×10−9for (8,0), for H2; and 4.5×10−17for (0,0), 1.4×10−14for (0,20), and 6.0×10−9for (11,0), for D2.

ISSN:0003-6951    

DOI:10.1063/1.91023

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Electron attachment to F2and NF3has been studied in an electron‐beam‐controlled gas‐discharge apparatus over a range ofE/P(2–10 kV/cm atm). These experiments were performed in gas mixtures containing small amounts of the halide molecules (≲1%) in an atmosphere of N2which was included to control the average electron energy. We obtained values for the rate constants for dissociative attachment to F2and NF3as a function of mixture temperature at 300 and 500 °K and applied electric field. These results compare favorably with the rate constants deduced from the absolute cross section for these compounds reported by Chantry.

ISSN:0003-6951    

DOI:10.1063/1.91005

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

SiC(6H) crystals amorphized with14N+‐ion implantation were annealed with CO2laser pulses at intensities of 20–100 MW/cm2. Laser produced crystallization due to residual ray absorption was studied by means of optical spectroscopy,4He+‐ion backscattering spectrometry and channeling as well as Cu K&agr;1and synchrotron x‐ray diffraction topography. At low laser intensities topographs revealed linear and planar defects, which contributed to increased dechanneling independent of analyzing beam energy. Minimum of lattice disorder, which was in some regions of the laser impact area smaller than that obtained in thermal annealing, was attained at the peak laser intensities of about 50 MW/cm2.

ISSN:0003-6951    

DOI:10.1063/1.91006

出版商:AIP    

年代:1979

数据来源: AIP