摘要:

The factors causing glow‐to‐arc transition in volume‐dominated molecular gas discharges have been analyzed in terms of the collisional processes taking place in the plasma. It has been shown that arcing can be initiated by the growth of disturbances in either vibrational or translational temperature. Calculations indicate that thermal and/or vibrational instabilities will occur for most conditions of importance to high‐power cw CO2convection lasers, and that the growth time for these instabilities is typically on the order of 1 msec.

ISSN:0003-6951    

DOI:10.1063/1.1655338

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

The low‐frequency interaction of a cross‐field current with a longitudinally magnetized inhomogeneous plasma has been studied. It is found experimentally that, in addition to the ion‐cyclotron harmonic instability, a very low‐frequency instability also develops in the range&ohgr;2≪ &ohgr;c i2, &ohgr;c ibeing the ion‐cyclotron frequency, and that at these large amplitudes nonlinear wave mixing takes place between them. Using a simple model, we show that the latter mode can be interpreted in terms of the cross‐field current‐driven modified ion‐cyclotron instability.

ISSN:0003-6951    

DOI:10.1063/1.1655339

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

An empirical corresponding states relationship between the ratio of the heat capacitiesCp/Cvof polymers and the reduced temperatureT/Tghas been found. This relationship is discussed in terms of corresponding states behavior. This relationship is significant and useful in that the ratioCp/Cvis a fundamental quantity for a solid polymer and a knowledge of the value of this ratio is useful for converting adiabatic data into the corresponding isothermal values and vice versa.

ISSN:0003-6951    

DOI:10.1063/1.1655340

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

We have computer simulated the structure of thin amorphous films grown from a vapor. Our hard‐sphere model shows that structural anisotropy and voids are a natural occurrence of the deposition process. The amount of unfilled space (voids) and the anisotropy have been studied as a function of the angle of incidence of the vapor stream upon the substrate.

ISSN:0003-6951    

DOI:10.1063/1.1655341

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Using Bragg's rule of additivity of the stopping powers in compounds and the Rutherford backscattering technique to determine electronic stopping powers, the depth distribution of 4‐keV helium ions implanted in niobium was determined for different implantation temperatures.

ISSN:0003-6951    

DOI:10.1063/1.1655342

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

A method of obtaining efficient photoemission in the wavelength region from 1 to 2 &mgr;m, using the transferred‐electron effect in ap‐type semiconductor, is proposed. Experimental demonstration of emission from InP in this mode is reported.

ISSN:0003-6951    

DOI:10.1063/1.1655343

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

A technique is described by which light entering a thin film is ``trapped'' in the sense of having to traverse the film a number of times. It is shown that the use of this technique in silicon provides a solar cell with good carrier collection efficiencies even with Si only ∼2 &mgr;m thick and with ∼10‐nsec lifetime.

ISSN:0003-6951    

DOI:10.1063/1.1655344

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Operation of a pulsed HF chemical laser initiated by electric discharge is reported. Uniform transverse capacitive discharge through high‐pressure mixtures of SF6and H2is effected by the use of a double discharge. For the mixture SF6, H2, He (250, 20, and 280 Torr, respectively) laser output of more than 1 J per pulse with 4% electrical efficiency from an active volume of 0.06 1 has been achieved. Pulse shapes of the different transitions, spectrum measurements, and SF6decomposition rate are reported.

ISSN:0003-6951    

DOI:10.1063/1.1655345

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Criteria and tolerances are discussed for realizing grating filters with bandwidths as narrow as 0.1 Å. Techniques are presented for minimizing the adverse effect of film thickness variations which broaden filter response and raise out of band ripple. Using these techniques a grating filter fabricated on a glass thin‐film waveguide is demonstrated which has 73% reflectivity and a 3‐dB bandwidth of 0.15 Å.

ISSN:0003-6951    

DOI:10.1063/1.1655346

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

A coherent tunable vacuum ultraviolet picosecond source has been constructed by third‐order nonlinear mixing of a broadly tunable picosecond visible source and the fourth harmonic of a mode‐locked Nd : YAG laser in xenon. Tunable radiation in the VUV covering portions of the region from 1180 to 1470 Å and continuously from 1631 to 1946 Å is obtained.

ISSN:0003-6951    

DOI:10.1063/1.1655347

出版商:AIP    

年代:1974

数据来源: AIP