摘要:

An experiment is described to measure directly the mean free lifetime of the photoexcited carriers in a semi‐insulating crystal by monitoring its photoconductivity.

ISSN:0003-6951    

DOI:10.1063/1.89541

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Raman backscattering from oxidized GaAs and InAs yielded two anomalous peaks of large scattering strength which we have concluded to be from excess As in the interface between the oxides and underlying semiconductors. Similarly, we concluded that the two anomalous peaks from GaSb and InSb are from excess interface Sb. From the frequencies, line shapes, and polarization selection rules, we deduced that the excess As and Sb are in the crystalline semimetal phase, as distinct from the amorphous phase.

ISSN:0003-6951    

DOI:10.1063/1.89542

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Nonlinearity (kinks) in the dependence of light output power on current has been effectively eliminated by the use of mirrors aligned at a small angle from the direction perpendicular to the stripe or filament. Such a structure increases confinement of the lasing filament and causes an increase in threshold current density that is smaller than that produced by stripe narrowing.

ISSN:0003-6951    

DOI:10.1063/1.89543

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

The electrical and optical properties of rf‐sputtered Sn‐doped In2O3(ITO) films have been found to depend strongly on the O2partial pressure during deposition. For the sputtering conditions used, films with both low electrical resistivity (&rgr; ∼ 3 × 10−4&OHgr; cm) and high visible transmission (∼ 90%) were obtained only over a narrow range of O2pressures, from 3 × 10−5to 4 × 10−5Torr. Our results appear to explain the difficulties that have previously been encountered in obtaining high‐quality ITO films, and indicate that control of the O2pressure during deposition is essential for reproducible preparation of such films.

ISSN:0003-6951    

DOI:10.1063/1.89544

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

An unbiased Josephson tunnel junction, irradiated with microwaves, can spontaneously develop quantized dc voltages. We explain this effect with reference to the shunted junction model and to analog experiments. This effect may be utilized to significantly improve both the accuracy and the simplicity of the Josephson voltage standard.

ISSN:0003-6951    

DOI:10.1063/1.89520

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

An analysis for the propagation characteristics of the magnetostatic surface waves in a YIG slab having periodically corrugated surfaces is presented. The Brillouin diagrams, close to the intersection point (&ohgr;,&bgr;) ofm=0 andm=−1 space harmonics, are obtained for different strengths of modulation. Comparison between the magnetostatic surface waves and volume waves concerning the complex value of the propagation constant within the stop band is also discussed.

ISSN:0003-6951    

DOI:10.1063/1.89545

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

Experiments in the 3‐GHz region are reported for oblique incidence of magnetostatic forward volume waves (MSFVW) on an 8‐period uniform metallic grating of 140 &mgr;m periodicity. The MSFVW propagate in a 25‐&mgr;m‐thick epitaxial yttrium iron garnet film under normal magnetic bias. Insertion loss data and observed bandpass response are reasonably consistent with theory for MSFVW reflection through 90° by an array possessing a periodic impedance discontinuity.

ISSN:0003-6951    

DOI:10.1063/1.89546

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

The covariance function of a stationary and homogeneous random field, represented by an analytic signal, is related to its wave‐number spectrum moments. By using a pair of fixed probes with an appropriately small separation, one can estimate the mean wave number and the wave‐number spectral spread. This method may be useful for the experimental study of fluctuation phenomena in plasmas, fluids, etc.

ISSN:0003-6951    

DOI:10.1063/1.89547

出版商:AIP    

年代:1977

数据来源: AIP

摘要:

The use of synchrotron radiation is shown to give promising properties to x‐ray absorption microanalysis. Geological samples, 30 &mgr;m thick, have been analyzed over large areas with a few micrometers resolution, and maps of transition‐metal distributions were obtained in less than 15 min. An increased resolution is expected with x‐ray resists.

ISSN:0003-6951    

DOI:10.1063/1.89519

出版商:AIP    

年代:1977

数据来源: AIP

ISSN:0003-6951    

DOI:10.1063/1.89813

出版商:AIP    

年代:1977

数据来源: AIP