摘要:

A Ba2Ge2TiO8single crystal is synthesized by the Bridgman method. The space group of Ba2Ge2TiO8is determined to beC2v21‐Iba2, where the lattice constantsa, b, andcare 12.30, 135.2, and 10.70 Å, respectively. The crystal includes a wedge‐shaped domain structure which resembles those observed in Gd2(MoO4)3and Rochelle salt. BothXandYplates have a large electromechanical coupling factor in a thickness shear mode,k15= 0.27 andk24= 0.31.

ISSN:0003-6951    

DOI:10.1063/1.1654737

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Epitaxial layers of Ga0.66Al0.34As1−yPywithy≤ ≈ 0.04 have been grown in order to demonstrate that it is possible to adjust the lattice parameter of a mixed III‐V layer such that it is matched with the GaAs substrate atroom temperature. The amount of stress compensation has been determined as a function ofy, as well as estimates of the layer thicknesses required to suppress the formation of misfit dislocations.

ISSN:0003-6951    

DOI:10.1063/1.1654738

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The phase of an ultrasonic beam reflected from a liquid‐solid interface at and near Rayleigh angle incidence is measured using a new technique. Results indicate that two waves comprise the reflected beam, i.e., a specularly reflected wave and a reradiated surface wave, which do not change phase as the angle of incidence varies, which maintain a 180° phase difference between them, and which propagate collinearly only at the Rayleigh angle.

ISSN:0003-6951    

DOI:10.1063/1.1654739

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Self‐focusing of ruby laser light is studied as a function of sample length and temperature in the isotropic phase of nematic liquid‐crystal MBBA. The critical power for self‐focusing, 0.36 kW, observed near the phase transition temperature is a factor of 20 times less than that for CS2. The corresponding nonlinear index 4.4 × 10−10esu is the largest value known so far for any material.

ISSN:0003-6951    

DOI:10.1063/1.1654740

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Negative dilatation (shrinkage) induced by 10‐keV electron bombardment of SiO2films thermally grown on Si has been studied. Measured deflection changes in continuous SiO2bridges etched following irradiation showed a maximum shrinkage of [inverted lazy s] 0.8%, which occurred at 0.2 C/cm2, followed by a slight expansion, and subsequent saturation at higher exposures. Exposures up to 3 C/cm2were utilized. Isochronal annealing studies show the activation energy for recovery to be approximately 1 eV with 2% recovery occurring in 1 h at 400°C.

ISSN:0003-6951    

DOI:10.1063/1.1654741

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The elastic properties of single‐crystal grains in polycrystalline material can be studied through Brillouin scattering using a laser probe beam. The Brillouin spectra of hot‐pressed CaF2(Irtran‐3), having a typical grain size of 150 &mgr;m, is presented. We have observed scattering from both longitudinal and transverse phonons, despite the presence of a large elastically scattered signal, using a stable 3‐pass Fabry‐Perot interferometer having a contrast of 106.

ISSN:0003-6951    

DOI:10.1063/1.1654742

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

We have shown the feasibility of forming insulating walls in Ga1−xAlxAs by proton bombardment, and have demonstrated their stability up to a temperature of 180°C. The mean projected range of protons in Ga1−xAlxAs is determined for energies ranging from 200 to 1200 keV. The insulating properties of proton‐bombarded layers are applied to the realization of cross‐bar integrated arrays of electroluminescent diodes.

ISSN:0003-6951    

DOI:10.1063/1.1654743

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A short unconfined spark is imaged by a spherical reflector into a small dye cell. Lasing is achieved for electrical inputs as small as 5 mJ. Pulse repetition rates as high as 2000 pulses/sec (pps) have been attained. A tilted etalon permits wavelength tuning of the laser output.

ISSN:0003-6951    

DOI:10.1063/1.1654744

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Field‐effect mobility measurements on siliconn‐ andp‐channel MOS transistors at temperatures of 4.2 K and lower are reported. The measured field‐effect mobility as a function of the gate voltage shows an anomalous peaked structure superimposed on the well‐known over‐all behavior. These peaks are possibly due to statistical fluctuations within the bands of the semiconductor of the density of surface states as a function of the energy.

ISSN:0003-6951    

DOI:10.1063/1.1654745

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

High‐dose (300 keV) ion implant damage has been observed, by infrared microscopy, to extend approximately 1.4 times the junction depth or 4 times the projected range. No such damage has been seen for shallow implants that were diffused to a corresponding junction depth. Leakage currents were identical for both implant conditions. No ``tailing'' was identified in the profile that could explain the extent of damage.

ISSN:0003-6951    

DOI:10.1063/1.1654746

出版商:AIP    

年代:1973

数据来源: AIP