摘要:

Optical image scanning utilizing the phase modulation of a surface acoustic wave in a separated medium configuration of silicon on lithium niobate has been experimentally demonstrated with two similar techniques. In on e technique the long‐lived silicon surface states are charged and the image is scanned by a short counterpropagating acoustic pulse. In the second technique the surface states are charged by a short acoustic pulse but the image is scanned by a short pulse of uniform optical illumination.

ISSN:0003-6951    

DOI:10.1063/1.88606

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

The spectral dependence of positive space charge induced in an Al‐Al2O3‐Si MOS structure shows a sharp threshold at 7.8±0.2 eV. This threshold is interpreted to be the onset of band‐to‐band transitions in Al2O3. The net space charge induced by 10.2‐eV radiation can be positive or negative depending on the bias polarity and magnitude. The voltage dependence is qualitatively explained by the competitive processes of electron‐hole pair generation and electron injection from the electrodes.

ISSN:0003-6951    

DOI:10.1063/1.88607

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

A modified method for the preparation of low‐loss optical fibers by means of chemical vapor deposition (CVD) techniques has been developed. In this method, a nonisothermal plasma is used to stimulate the reactions. Deposition of oxides then occurs only heterogeneously on the substrate. Results obtained by this method show optical losses well below 10 dB/km—having a minimum of 1.4 dB/km at a wavelength of 1050 nm—and a pulse dispersion of 0.8 ns/km.

ISSN:0003-6951    

DOI:10.1063/1.88608

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Impurity‐assisted red‐green conversion has been observed in CdS with excitation intensities less than 1 &mgr;W. After red illumination, energy is stored in the crystals for times in the order of hours. The stored energy is detectable as green emitted light by infrared excitation.

ISSN:0003-6951    

DOI:10.1063/1.88609

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

We reportabinitiocalculations on the electronic states of KrF arising from the Kr+F, Kr++F−, and Kr*+F separated atom limits. We conclude, in agreement with earlier assignments, that the observed laser transition isC(1/2) ‐X(1/2) (5.15 eV calculated, 5.00 eV observed). The calculated lifetime of theC(1/2) state is 6.5 ns. The ionic2&Pgr; state was found to lie close to the ionic2&Sgr;+state.

ISSN:0003-6951    

DOI:10.1063/1.88610

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Phase‐matched second‐harmonic generation in solid thin films has been achieved by using gratings etched onto the surface of a nonlinear substrate to modulate the nonlinear susceptibility.

ISSN:0003-6951    

DOI:10.1063/1.88611

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

A linearly pumped methyl fluoride laser oscillator‐amplifier is described which yields a peak power of 30 kW in a linewidth <60 MHz. Linear pumping results in nearly complete saturation of the FIR transition and consequently in relatively high photon conversion efficiency, which in the present case is 70% of its maximum theoretical value at operating pressures of 2–3 Torr. The present result indicates that MW‐level peak power, such as required for plasma‐ion scattering experiments, may be achieved using less than 140 MW of CO2laser pumping power (<14 J in 100 nsec) in an amplifier less than 2 m long.

ISSN:0003-6951    

DOI:10.1063/1.88612

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Laser action on theE→Bband of molecular bromine at 292 nm has been observed in anE‐beam‐controlled discharge. The laser mixture was 99.6% Ar and 0.4% Br2at a pressure of 4 atm. The mean discharge current and voltage were 25 A/cm2and 11 kV/cm, respectively. The high‐energyE‐beam current density was 1.5 A/cm2. The mechanisms for creating Br2* in a discharge are discussed.

ISSN:0003-6951    

DOI:10.1063/1.88613

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

The design and operation of a pulsed high‐power narrow‐line CH3F oscillator‐amplifier laser system is described. The dielectric waveguide oscillator produces output in a single longitudinal mode with linewidth less than 40 MHz and sufficient power (∼11 kW) to saturate the far‐infrared emission transition at the amplifier input. Pumped by ∼8 J of CO2, the amplifier has produced up to 156 kW of narrow‐line 496‐&mgr;m output. The amplifier gain is found to be sensitively dependent upon the relative timing of the FIR oscillator and CO2pump pulses.

ISSN:0003-6951    

DOI:10.1063/1.88604

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

A design is reported for a compact and simply constructed CO2TEA laser giving pulses of up to 50 J with 0.1‐&mgr;s duration from a discharge of dimensions 45×6×6 cm3. The gas is preionized by VUV irradiation from two lines of 34 series arcs to either side of the uniform field electrodes to which potentials of +50 kV and −50 kV are applied. The mechanism of preionization and the conditions for a uniform discharge are considered.

ISSN:0003-6951    

DOI:10.1063/1.88605

出版商:AIP    

年代:1976

数据来源: AIP