摘要:

Zero‐phonon transitions at 0.79 and 0.97 eV observed in electron‐irradiated silicon have been ascribed by previous workers to theKcenter and the divacancy, respectively, on the basis of their production and annealing behavior. This paper shows that, contrary to the original interpretation, the uniaxial stress results on these lines indicate monoclinic symmetry, which is consistent with the proposed models. The stress results on a third zero‐phonon line at 1.045 eV are reinterpreted.

ISSN:0021-8979    

DOI:10.1063/1.1663107

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Recent experimental and analytical results indicate that the 0.97‐eV luminescence from irradiated Si is characterized by monoclinic symmetry. The assignment of symmetry class for other luminescence peaks in this material is incomplete.

ISSN:0021-8979    

DOI:10.1063/1.1663108

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

We propose that the application of an external temperature gradient to a semiconductor can lead to the amplification of the acoustic wave.

ISSN:0021-8979    

DOI:10.1063/1.1663109

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Low‐temperature values of the magnetocrystalline anisotropy constantK1for several nickel ferrous ferrites were measured using the torque method. These were compared to existing microwaveK1values for the same crystals. The incremental &Dgr;K1=K1(torque)‐K1(microwave) were found to increase to well‐defined maxima below 77°K and then to decrease toward zero at 4.2°K. The temperature at which the maximum value of &Dgr;K1occurred increased with increasing Fe2+concentration. The low‐temperature maxima and subsequent sharp decreases in &Dgr;K1cannot be fit to earlier theory which was successful above 77°K. This indicates the loss mechanism responsible for &Dgr;K1at higher temperatures becomes inoperative at liquid‐helium temperatures. The maximum value of &Dgr;K1is found to depend on the Ni2+concentration as well as Fe2+concentration. This suggests that the Ni2+ions may also be involved in the relaxation mechanism responsible for &Dgr;K1.

ISSN:0021-8979    

DOI:10.1063/1.1663110

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Preliminary measurements of the time‐dependent light emission from aerosol particles (generated from submicron powders of carbon black and alumina) during excitation with pulses from a TEA CO2laser show that this emission may be simply related to particle size.

ISSN:0021-8979    

DOI:10.1063/1.1663111

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

A lead‐vapor laser utilizing lead chloride as a lasant has been investigated. Lasing is attained by means of two consecutive electrical discharges. The maximum output is obtained at a vapor pressure of about 0.3 Torr at a temperature of 500°C, a time delay between electrical discharges of 150 &mgr;s, and an output mirror transmittance of 80%. The maximum energy density and power density are respectively 4 &mgr;J cm−3and 160 W cm−3.

ISSN:0021-8979    

DOI:10.1063/1.1663112

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Magnetostatic wave propagations in parallel layers of magnetic slabs have been considered. The dispersion characteristics depend strongly on the separation between slabs and their respective crystal plane orientations. The frequency range for nondispersive magnetostatic wave propagation can be extended as compared to the range obtained from the single slab. Magnetic interactions between magnetostatic waves can be studied directly in this configuration.

ISSN:0021-8979    

DOI:10.1063/1.1663113

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

A criterion of the onset of switching in the amorphous semiconductor threshold switch is given. This criterion arises from the condition for the onset of one phonon‐assisted hopping of small polarons.

ISSN:0021-8979    

DOI:10.1063/1.1663114

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

As and B were implanted inton‐type Si at 40 keV. The shallow layer was used as a source for simultaneous diffusion and formation of an‐p‐nstructure. The diffusion coefficients obtained were the same as those for the diffusion of the individual dopants. It is suggested that this technique may be of interest for the formation of complex profiles which are too deep to be obtained by implantation alone.

ISSN:0021-8979    

DOI:10.1063/1.1663115

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

The conversion efficiency of solar cells made of organic semiconductors with metallic electrodes on opposite surfaces is calculated on the basis of a model of two diodes connected in series, but with opposite polarity. We find that the intrinsic conversion efficiency would be two orders of magnitude higher than the conventional value of 10−5–10−6if the presently used solar‐cell configuration of organic semiconductors could be altered to have an Ohmic contact on one surface.

ISSN:0021-8979    

DOI:10.1063/1.1663116

出版商:AIP    

年代:1974

数据来源: AIP