摘要:

Intense Stark resonance absorptions near 10.7 &mgr;m of theR(18) andR(24) lines and a weaker absorption of theR(26) line of the isotopic C13O216laser by N14H3are reported. Wideband modulation experiments with an N14H3Stark cell and theR(18) line are presented. Key modulation features are the 2‐ns rise time, high modulation depths, low power dissipation, short Stark modulator cell (10 cm), high saturation intensity (≳8 W/cm2), new spectral features of the modulated signal versus Stark bias, and a demonstration of 180‐Mbit random word modulation.

ISSN:0003-6951    

DOI:10.1063/1.89302

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

By measuring the equilibrated sustainer current density in F2/N2mixtures under controlled discharge conditions, we have determined the F2dissociative attachment rate constant at variousE/Pconditions. The F2+e→F∓F rate constant at an average electron energy of 1.0 eV was found to be 2.3±0.3×10−9cm3/molecule/sec and increased with decreasing electron energy.

ISSN:0003-6951    

DOI:10.1063/1.89303

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

A mechanism is proposed to explain the improvement in discharge uniformity observed in pure electric‐discharge‐pumped rare‐gas halide lasers when a uv preionizer is used to precondition the laser medium. In the model the F−ions formed by dissociative attachment following uv photoionization act as a reservoir from which electrons are easily released when the main discharge field is applied. The model shows that a time delay is required between the application of the uv and the main discharge, and also that the effect of the preionizer can last some tens of microseconds despite the large electron attachment rates in the laser mixture.

ISSN:0003-6951    

DOI:10.1063/1.89304

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Chlorine has been incorporated into SiO2films by thermal oxidation of Si in a mixture of O2and HCl gases. Mobile sodium ions adsorbed on the oxide surface were drifted to the Si‐SiO2interface (0.5 MV cm−1bias at 200 °C). Passivation, defined as the fraction of mobile sodium charge neutralized, exhibited a pronounced threshold with HCl content in the growth ambient. This was partly due to a similar variation of oxide chlorine content (measured by &agr;‐particle backscattering). For fixed growth temperature, passivation was a monotonic function of oxide chlorine content, and was only weakly dependent on the level of sodium contamination over the range 5×1011to 1×1013Na/cm2.

ISSN:0003-6951    

DOI:10.1063/1.89305

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

A new device, the charge‐flow transistor (CFT), has been developed to achieve integrated MOS compatibility in sensor applications, such as gas, humidity, and fire detection, where one is interested in monitoring the transverse resistance of a thin film. The resistive material is incorporated into the gate structure of the CFT in such a way that there is a time delay between the application of the gate‐to‐source voltage and the appearance of a complete channel. This time delay depends on the resistivity of the thin film. A theory of device operation is presented, together with experimental results on the first CFT’s. These results confirm the principles of operation, and demonstrate the utility of the CFT for making fully integrated sensing devices.

ISSN:0003-6951    

DOI:10.1063/1.89306

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

p‐CuGaSe2/n‐CdS heterojunctions have been prepared by depositing CdS films onp‐type CuGaSe2single crystals whose initial resistivity was 10−2&OHgr; cm and changed to 1 &OHgr; cm after the CdS film deposition. The CdS films, which were grown by a multisources method, exhibit a room‐temperature resistivity of 0.1 &OHgr; cm. The absolute quantum efficiency of these devices as photovoltaic detectors reaches the value of 80% at a wavelength of 5800 A˚. As solar cells, these heterojunctions at 25 °C display a solar power conversion efficiency of 5% when they are exposed to the solar light whose intensity is 71 mW/cm2. When the heterojunctions are directly polarized, they emit light in a broad band which is centered at ∼7700 A˚. An external electroluminescent emission efficiency of about 0.05% has been measured at liquid‐nitrogen temperature.

ISSN:0003-6951    

DOI:10.1063/1.89307

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Simple oxide‐insulated stripe‐geometry double‐heterostructure lasers have been made and life tested as part of an extensive laser reliability program. Early lasers have now been on test for more than 13 000 h and the first batch test has exceeded 7000 h. All the batch test lasers show slow degradation and at least 85% have rates of increase of threshold below 3.3% per 1000 h. Simple visual prebonding selection was used to eliminate defective lasers, and these results demonstrate that within this limitation lives in excess of 7000 h can be consistently achieved.

ISSN:0003-6951    

DOI:10.1063/1.89308

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

A semiconductor laser having a narrow emission bandwidth (<1 A˚) with center wavelength electronically tunable over a large spectral range is demonstrated for the first time. This electro‐optically tunable infrared semiconductor laser source should have interesting applications in, for example, optical communications systems, optical radar, and spectroscopy.

ISSN:0003-6951    

DOI:10.1063/1.89309

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Recently published data concerning a contemporary well‐behaved cw stripe‐geometry injection laser was accompanied by the assertion that above threshold both the junction voltage and the spontaneous emission exhibit ’’complete saturation’’. This paper shows by detailed analysis of the data that in fact the small incompleteness of the saturation agrees with the value predicted by the new nonlinear theory of injection lasers. The junction voltage, spontaneous emission, and mode powering of this cw laser are interconnected by the theory just as they were in the various types of pulsed lasers already described.

ISSN:0003-6951    

DOI:10.1063/1.89310

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Significant improvements in gain and energy resolution are reported for very‐large‐areap‐n‐junction‐type silicon avalanche radiation detectors which were made from neutron‐doped silicon. Detectors with frontal areas of about 20 mm2had gains which ranged from 400 (1.2 keV FWHM at 5.9 keV) to over 800 (2.2 keV FWHM at 5.9 keV). A 330‐mm2device showed a maximum gain of 150 with an energy resolution of 16 keV FWHM at 22 keV.

ISSN:0003-6951    

DOI:10.1063/1.89288

出版商:AIP    

年代:1977

数据来源: AIP