摘要:

Cross sections &sgr; for the photoionization of metastable rare‐gas atoms (He*‐Xe*) over a wide range of photon energies are presented. In marked contrast to that found for He* where &sgr;∼10−18cm2and decreases monotonically with photon energy, the cross sections &sgr; for Ne*‐Xe* are much smaller ∼10−19cm2and exhibit optical windows within the wavelength range 2000–3000 A˚ of current laser interest.

ISSN:0003-6951    

DOI:10.1063/1.89794

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Holograms have been recorded with far‐infrared radiation (10.6 &mgr;m) on ’’Takiwax’’ films. The relief‐phase holograms obtained due to the thermal process involved are reconstructed, in real time, with He‐Ne laser light. Reconstruction from grating holograms in the infrared with 10.6‐&mgr;m CO2laser radiation is also possible: diffraction efficiencies of up to 15% have been measured for two‐beam gratings.

ISSN:0003-6951    

DOI:10.1063/1.89795

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

We report the use of the two‐photon magnetoabsorption effects due to excitons in CdS to obtain a fast modulator for a CO2laser beam. The modulator is controlled by short optical pulses from a visible‐light dye laser. 4‐nsec pulses of 75 W peak power of a CO2laser beam have been produced by using this technique which is potentially capable of generation of psec optical pulses in the infrared.

ISSN:0003-6951    

DOI:10.1063/1.89796

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Millimeter and submillimeter microwave spectroscopy is shown to be a powerful technique for the study of the fundamental processes of molecular lasers. The calculation of absolute chemical compositions, excitation parameters, and the observation of collisional deexcitation are demonstrated for the HCN FIR laser.

ISSN:0003-6951    

DOI:10.1063/1.89797

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Laser action was achieved on theB 2&Sgr;+→X 2&Sgr;+transition of the HgBr radical by photodissociating HgBr2in the vapor phase. The pump radiation was the 193‐nm output of an ArF excimer laser. The measured laser wavelengths range from 502 to 505 nm. In transverse excitation, the measured output energy of the HgBr laser was 0.25 mJ at a pump energy of 7 mJ.

ISSN:0003-6951    

DOI:10.1063/1.89798

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Au(evaporated film) ‐semiconductor(substrate) systems were studied by Auger electron spectroscopy. For semiconductors with energy gaps (Eg) smaller than ∼2.5 eV, even at room temperature a considerable fraction of atoms constituting the semiconductors were found to accumulate on the surfaces of Au films, indicating ready interfacial interaction between these materials. Study of the interface regions of the above systems verified the occurrence of the room‐temperature interfacial reactions.

ISSN:0003-6951    

DOI:10.1063/1.89799

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Highly collimated laser beams have been observed to be coupled out by second‐order Bragg scattering from GaAs distributed Bragg reflector lasers. The beams are perpendicular to the waveguide plane and have an angular width of less than 1°. The diodes have a separate confinement structure and operate at room temperature with thresholds as low as 1.4 kA/cm2.

ISSN:0003-6951    

DOI:10.1063/1.89800

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

This paper describes a process for the laser machining of thin metallic films on dielectric substrates. The observation of a distinct minimum in the machining threshold and the fact that no substrate damage occurs over a wide range of incident power are explained based on an explosive film‐removal mechanism. Experimental results supporting the predictions are presented.

ISSN:0003-6951    

DOI:10.1063/1.89801

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Heavy boron diffusion followed by selective etching has been used to produce uniform edge‐supported Si diaphragms with thickness in the 1–3‐&mgr; range and areas up to 5 cm2. These diaphragms have numerous applications in the fabrication of rugged reliable electromechanical devices which are compatible with IC technology. In this paper we describe the performance of an electrically tunable resonant cavity which operates in the 10–12‐kHz range withQas high as 23 000. Devices based on this cavity structure include pressure transducers, microphones, speakers, tunable filters, and oscillators.

ISSN:0003-6951    

DOI:10.1063/1.89802

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Schottky‐barrier photodiodes were prepared by depositing either lead or indium ontop‐type PbSxSe1−xepitaxial films. These photodiodes had 77 °K zero‐bias resistance‐area products of 26–21 000 &OHgr; cm2asxvaried from 0 to 1, respectively. The peak detectivities were close to the background limit and could be composition tuned between 3.7 and 6.9 &mgr;m at 77 °K. Narrowband detectors were prepared by using one film as a short‐wavelength cutoff filter and a second film, of slightly different composition, as the detector. These devices exhibit high quantum efficiencies, low half‐bandwidths, and insensitivity to variations in incident angle.

ISSN:0003-6951    

DOI:10.1063/1.89773

出版商:AIP    

年代:1977

数据来源: AIP