摘要:

It is demonstrated that even in the case of weak polar coupling, certain two‐phonon scattering processes lead to rates comparable to one‐phonon scattering. This additional scattering will influence the electron distributions and velocity‐field characteristics calculated for polar semiconductors.

ISSN:0003-6951    

DOI:10.1063/1.1754948

出版商:AIP    

年代:1967

数据来源: AIP

摘要:

The transient response of semi‐insulating CdTe to monoenergetic alpha particles is composed of a fast component, characteristic of trapping, and slow component displaying the release of carriers from traps. It is verified that the shape of the fast component is directly proportional to [1 ‐ exp (‐t/&tgr;+)] for electrons where &tgr;+is the mean free drift time. From an analysis of the shape, &tgr;+for electrons ranges from 30 to 90 nsec; mobilities from 600 to 1100 cm2/V‐sec. On a single‐level model thermal and optical excitation data indicate a trapping level at 0.6±0.05 eV from the conduction band.

ISSN:0003-6951    

DOI:10.1063/1.1754949

出版商:AIP    

年代:1967

数据来源: AIP

摘要:

Diffraction of light at 1.15 &mgr; has been observed from magnetoelastic waves at 1.1 GHz in YIG. A shift in the Bragg diffraction angle was observed when an external magnetic field was varied so as to change the spin wave admixture. The largest shift obtained experimentally was ‐2.0°, measured from the elastic limit of 9.5°. This shift was accompanied by a delay in the diffracted pulse of about 1 &mgr;sec. Under quasielastic conditions the diffracted intensity exhibited a series of maxima as the field was swept, due to magnetoelastic Faraday rotation.

ISSN:0003-6951    

DOI:10.1063/1.1754950

出版商:AIP    

年代:1967

数据来源: AIP

摘要:

High energy electrons penetrating a solid and emerging from a surface can remove surface atoms by Coulomb interaction with their nuclei. Observations of this desorption process were made on a (100) tungsten surface with an adsorbed layer of thorium atoms of known coverage. Electrons of energy up to 2 MeV were used and the rate of removal of thorium atoms was calculated from the rate of change of work function of a collector surface. Measurements of desorption rate as a function of energy suggest a binding energy of 15 to 20 eV, in contrast to the 8 eV obtained from thermal desorption.

ISSN:0003-6951    

DOI:10.1063/1.1754951

出版商:AIP    

年代:1967

数据来源: AIP

摘要:

Thin single‐crystal films of cubic silicon carbide have been grown on silicon substrates within the temperature range 800‐ 1000°C in high and ultrahigh vacuum by the reaction of unsaturated hydrocarbons, C2H and C2H4with silicon. The cubic silicon carbide grows with a parallel orientation onto silicon, regardless of crystal orientation. The use of ultrahigh vacuum results in high crystal perfection.

ISSN:0003-6951    

DOI:10.1063/1.1754939

出版商:AIP    

年代:1967

数据来源: AIP

摘要:

Thin‐film aluminum resistors with thermally grown SiO2as the substrate have been subjected to very high current densities of the order 0.5 to 2 × 106A/cm2. The temperature of the resistor is estimated to be (185 ± 15)°C at high current densities. It is observed that an opening occurs in most of these resistors close to the cathode. Experimental evidence is presented to show that electromigration leads to the observed failures in these thin‐film aluminum resistors.

ISSN:0003-6951    

DOI:10.1063/1.1754940

出版商:AIP    

年代:1967

数据来源: AIP

摘要:

Good quality three‐dimensional reconstructed images of diffusely reflecting objects were obtained by recording a hologram withQ‐switched pulsed ruby laser illumination and viewing it with He&sngbnd;Ne laser light.

ISSN:0003-6951    

DOI:10.1063/1.1754941

出版商:AIP    

年代:1967

数据来源: AIP

摘要:

Laser action has been observed on pure rotational transitions of HF formed by a chemical reaction in an electrically pulsed discharge. The wavelengths, lying between 10.2 and 21.8 &mgr;, are listed and identified.

ISSN:0003-6951    

DOI:10.1063/1.1754942

出版商:AIP    

年代:1967

数据来源: AIP

摘要:

Four real images were reconstructed from a coarsely sampled acoustical hologram made with an ordinary microphone. An internal reference was used which electronically simulated two plane reference waves impinging on the acoustical hologram plane at an angle of + and ‐42.55° from the perpendicular. The sound frequency was 20 kHz, with a wavelength of 0.676 in. in air.

ISSN:0003-6951    

DOI:10.1063/1.1754943

出版商:AIP    

年代:1967

数据来源: AIP

摘要:

Linear electro‐optic coefficients as large asr∼ 4 × 10‐5cm/statvolt have been measured in the system of ferroelectric strontium barium niobates, SrxBa1‐xNb2O6. In the first crystalsxvaries from 0.75 to 0.25, with Curie temperatures ranging from ∼60°C to 250°C. At 15 Mc, the respective half‐wave field distance products range from 48 to 1236 V.

ISSN:0003-6951    

DOI:10.1063/1.1754944

出版商:AIP    

年代:1967

数据来源: AIP