摘要:

An MIS structure, in which the semiconductor is suitably doped ZnSe, exhibits switching and memory properties. The same structure also emits light in both forward and reverse bias with an emission wavelength characteristic of the impurities present. Although the operation of the device is not completely understood the switching can be attributed to a transfer of charge from deep impurities in the semiconductor to the insulating layer.

ISSN:0003-6951    

DOI:10.1063/1.1654112

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

In a recent experiment on laser beam transmission through an absorbing gas, the critical Reynold's number for the flow, induced by the heating of the gas, to become turbulent was found to be less than 30, which is many orders of magnitude smaller than that for pure shear flow in pipes. It is shown here that a Rayleigh number is the more appropriate criterion to characterize the stability of flow in this situation, and its value estimated in two limiting cases is found to bracket the expected critical Rayleigh number for vertical concentric cylinders.

ISSN:0003-6951    

DOI:10.1063/1.1654113

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Direct experimental measurement of surface‐wave scatter losses of several ceramics is reported, as well as verification of the fourth‐power frequency dependence of scatter losses per wavelength predicted by Steg and Klemens. Laser measurements of surface‐wave amplitude vs position exhibit interference due to scattered waves. The statistical analysis of such measurements allows separation of scatter losses from true dissipative losses. Scatter losses for Honeywell Type S material are found to be 0.027 dB/wavelength at 46.8 MHz, and increase with the fourth power of frequency. A limiting frequency for a given ceramic for surface‐wave applications might be the frequency at which scatter losses overtake dissipative losses; for Honeywell S, this occurs at 73 MHz.

ISSN:0003-6951    

DOI:10.1063/1.1654114

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Dielectric optical waveguides have been made by embossing grooves in a thermoplastic substrate and filling them with a liquid which is then solidified. Grooves (7 &mgr;m wide and 3.5 &mgr;m deep) in poly(methyl methacrylate) (n=1.49) were filled with cyclohexyl methacrylate which was photopolymerized to produce a permanent guide (n=1.505). The attenuation was 2–4 dB/cm at &lgr;=0.633 &mgr;m.

ISSN:0003-6951    

DOI:10.1063/1.1654115

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

The existence of a new type of surface sound wave—pure shear surface sound wave—is predicted for conducting solid materials. This wave arises due to the fact that in these materials the mechanical stress depends not only on the deformation but also on the electron concentration because of electron‐lattice interaction via the deformation potential. The penetration depth of this surface wave is of the order of &lgr;&egr;/&khgr;≫&lgr;, where &lgr; is the wavelength, &egr; is the dielectric constant, and &khgr; is the electromechanical coupling constant for the deformation‐potential interaction

ISSN:0003-6951    

DOI:10.1063/1.1654116

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Resistance changes associated with precipitation in Al&sngbnd;Cu thin films were monitored during power annealing at current densities up to 4×106A/cm2and temperatures of ∼178 and 200 °C. The rate of change of resistance decreased as the current increased. It is argued that this decrease is due to the current inhibiting the precipitation of &thgr; Al2Cu.

ISSN:0003-6951    

DOI:10.1063/1.1654117

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

An image‐tube streak camera has been further developed to be completely electronically operated, with an improved instrumental time resolution of <4 psec and negligible background. With a trigger pulse of 10 V and a rise time of 1 nsec, the over‐all system triggering jitter is <200 psec. The camera has been used to measure the durations of ultrashort pulses (2–3 psec) from a mode‐locked dye laser.

ISSN:0003-6951    

DOI:10.1063/1.1654118

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

The second harmonic of a 1.064‐&mgr; Nd3+YAG laser has been observed in paratellurite This effect is forbidden by Kleinman's relations. The only nonvanishing nonlinear coefficientd14has been measured relative to quartz by the Maker‐fringe technique and to KDP under phase‐matching conditions. It has been inferred thatd14=1.4×10−9esu and &dgr;14=3.8×10−8esu. The latter value is 40 times lower than the average over all the known materials.

ISSN:0003-6951    

DOI:10.1063/1.1654119

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Measurements of the velocity‐electric field characteristic ofn‐type InP at 9.5 and 35 GHz are reported. The results indicate a peak velocity of about 2.7×107cm/sec and threshold field of 12 kV/cm. The measurements are in good agreement with a two‐valley model of conduction.

ISSN:0003-6951    

DOI:10.1063/1.1654120

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

The threshold pressure for breakdown of helium and argon gas by 10.6‐&mgr;m radiation from a TEA CO2laser is strongly depressed by a steady magnetic field parallel to the direction of propagation of the laser beam. At 87 kOe, the zero‐field threshold pressure is reduced from 166 to 96 Torr in helium and from 66 to 21 Torr in argon. This result can be explained semiquantitatively by a simple model of breakdown that takes into account the inhibition of radial electron diffusion by the magnetic field.

ISSN:0003-6951    

DOI:10.1063/1.1654121

出版商:AIP    

年代:1972

数据来源: AIP