摘要:

We report the observation of infrared Lamb dips using a widely tunable laser source. The microwave sidebands generated on CO2laser lines provide sufficient power (∼0.5 mW) and spectral purity (&Dgr;&ngr;≲100 kHz) for saturation spectroscopy. Application of this infrared source to the observation of infrared Lamb dip spectra of CH3F and SiF4is reported.

ISSN:0003-6951    

DOI:10.1063/1.94062

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A new technique to measure surface acoustic wave beam profiles is described. A measurement is made of the average phase change of the acoustic wave resulting from periodic heating of the sample surface by an incident modulated laser beam. Scanning of the laser beam across the acoustic wave results in a profile of the energy density in the acoustic beam. To measure the phase change, a surface acoustic wave oscillator configuration is used. Possible application of the technique to the measurement of applied and residual surface stress is discussed.

ISSN:0003-6951    

DOI:10.1063/1.94063

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

We have used an excimer laser to photodeposit uniform (±5%) films of zinc oxide from dimethylzinc and nitrogen dioxide. Deposition rates of 3000 A˚/min over 2 cm×5 cm areas were obtained. We have measured the stress, refractive index, etch rate, adhesion, pinhole density, and the stoichiometry of these photodeposited films.

ISSN:0003-6951    

DOI:10.1063/1.94064

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The glide mobility of dislocations in bulkn‐type InP single crystals was measured by the double‐etching method as a function of temperatures with or without 30‐keV electron beam irradiation. The mobility of &bgr; dislocations was found to be enhanced by the irradiation in such a manner that the mobility increase is caused by a decrease in the apparent activation energy, which is characteristic of recombination enhanced defect reaction phenomena. The enhancement is not much different in its magnitude from the same type of dislocations in GaAs.

ISSN:0003-6951    

DOI:10.1063/1.94065

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Carbon fibers of uniform diameter have been grown by pyrolysis of natural gas in type 304 stainless steel (18% Cr, 8% Ni) tubes at temperatures between 950 and 1075 °C. The method utilizes the circulation of wet hydrogen outside the growth tube in order to promote effective nucleation. Fibers 12 cm long having average moduli of 1.8×1011Pa have been grown.

ISSN:0003-6951    

DOI:10.1063/1.94066

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

In a homogeneous cell the origin of the steep decrease, which is always observed in the liquid crystal tilt angle on an SiO coating as a function of temperature in the range close toTc, is traced back to the growth of twist domains. It appears that a magnetic null method is unsuited for accurate tilt angle measurements in the relevant temperature region, because it is based on the assumption of a homogeneous director pattern in the sample cell.

ISSN:0003-6951    

DOI:10.1063/1.94067

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Amorphization by ion beam irradiation of multilayered samples of Al/Pt, Al/Pd, and Al/Ni has been investigated by selected area diffraction and Rutherford backscattering. With a dose of 2×1014Xe ions/cm2, uniform mixing is achieved in the Al/Pt system and the amorphous phase is produced over a large composition range. In the Al/Pd and Al/Ni systems, amorphous phases or the equilibrium, crystalline phases are formed depending on the composition of the films. The same results were found when the samples were annealed to form crystalline phases before bombardment. For thin films of these fcc metals, only the simplest intermetallics, NiAl and PdAl, (primitive cubic structures with 2 atoms/cell) were formed in crystalline form by ion‐beam irradiation.

ISSN:0003-6951    

DOI:10.1063/1.94068

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Spectral measurements over the wavelength range of 400–800 nm on As2S3, As2Se3, and GeSe2, measurements on a tuned structure of As2S3, and exact calculations on a multifilm structure support the recent suggestion that the photons relevant to the photodissolution of Ag are absorbed in the Ag and not in the chalcogenide. The observed spectral dependence may be fitted by an internal photoemission model.

ISSN:0003-6951    

DOI:10.1063/1.94051

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Amorphous silicon films have been prepared through mercury‐photosensitized decomposition of monosilane gas at low temperatures. The films show optical and electrical properties comparable with those of the best films prepared by plasma chemical vapor deposition. The feasibility of amorphous solar cells with short‐circuit current densities of more than 10 mA/cm2has been demonstrated by fabrication of a Schottky barrier structure.

ISSN:0003-6951    

DOI:10.1063/1.94069

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A photocapacitance method was used to monitor the time dependences of the occupation numbers for the gold‐related donor and acceptor in silicon during optical excitation. The experimental data give strong evidence that the donor level corresponds to the +/0 transition and the acceptor to the 0/− transition for one single defect.

ISSN:0003-6951    

DOI:10.1063/1.94070

出版商:AIP    

年代:1983

数据来源: AIP