摘要:

An epoxy−bonded LiNbO3−YIG−LiNbO3composite structure has been constructed and operated as a magnetoelastic Rayleigh wave convolver with 50−MHz input signals. The acoustic signals were propagated on a (110) YIG surface and the convolution characteristics were studied as a function of the magnitude and direction of the applied magnetic field. Nonuniform demagnetizing fields limited convolution pulses to less than 1.5 &mgr;sec duration. Relatively efficient operation was observed corresponding to an internal efficiencyFintof −53 dBm.

ISSN:0003-6951    

DOI:10.1063/1.88075

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Temperature−stable surface acoustic wave devices have been fabricated onYZ LiNbO3andYZ LiTaO3by the use of SiO2film overlays. On LiNbO3, a temperature dependence similar to that ofST−cut quartz was obtained, but with a coupling constantk2of at least 5.4%. On LiTaO3, a second−order temperature coefficient of delay that is 5 times smaller than and opposite in sign to that ofSTquartz was observed. The coupling constant was measured to be approximately 1.6%.

ISSN:0003-6951    

DOI:10.1063/1.88076

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

We have measured the distribution of boron in silicon, using secondary ion mass spectroscopy or nuclear reactions, after irradiation at 850°C by protons of energy 250−450 keV. The fluence was 1×1017to 6×1017protons/cm2. Prediffused and uniformly doped samples have been studied. It is found that the boron distribution is considerably modified: the boron concentration shows a peak near the end of the proton range, where the defect creation rate is highest. This anomaly cannot be explained by using solely simple diffusion theory, and depends on boron−defect interactions, such as the formation of precipitates or complexes. As a consequence, the interpretations of radiation−enhanced diffusion experiments must be discussed again.

ISSN:0003-6951    

DOI:10.1063/1.88077

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Conduction has been investigated in Al−Al2O3−Au sandwiches whose oxide is implanted with O or Al ions. The results reveal that ion implantation gives a junction type which can be electroformed, and which exhibits negative resistance in air at atmospheric pressure.

ISSN:0003-6951    

DOI:10.1063/1.88078

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

C−Vanalysis applied to a depletion layer bordering a semiconducting channel does not provide the true impurity distribution if the space−charge region penetrates to another depletion layer at the other side of the channel, i.e., if the channel is partially depleted. Cases in point are an epitaxial semiconducting channel on a semi−insulating chromium−doped gallium arsenide substrate; ann−channel on ap−substrate; and a heterojunction of a semiconducting epitaxial layer on an insulating substrate with interface states causing depletion.

ISSN:0003-6951    

DOI:10.1063/1.88088

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Heterojunctions have been fabricated by depositing glass films onto single−crystal silicon substrates. Junction behavior has been exhibited regardless of the electrical or chemical properties of the glass film. The observed characteristics are a function of these properties. Current rectification, variable capacitance, sharp reverse breakdown, and photovoltaic responses have been observed.

ISSN:0003-6951    

DOI:10.1063/1.88089

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Resonance self−absorption from overlapping lines in a CO laser medium may be an important pressure−dependent mechanism for theoretical analysis, with possible impact on line selection and atmospheric propagation. Certain presently unexplained discrepancies relating to transient time scale, spectral anomalies, efficiency degradation, and sensitivity to temperature might all be consistently resolved by this hypothesis.

ISSN:0003-6951    

DOI:10.1063/1.88090

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Here, we establish a relationG=gv/vEbetween the effective gain coefficientGin a periodic medium (for a Bloch wave) and the ordinary gain coefficientgin a corresponding uniform medium (for an ordinary plane wave). In distributed−feedback (DFB) lasers,Gis greater (or smaller) thangbecause the energy velocityvEof a Bloch wave is smaller (or greater) than the phase velocityvof a plane wave. The relation betweenGandgcan be regarded as a first principle for DFB lasers. We can use this principle to test the validity of a DFB−laser theory and to guide us to a correct interpretation of the theoretic result.

ISSN:0003-6951    

DOI:10.1063/1.88091

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

An optical Kerr gate is operated at high repetition rates using picosecond pulses from a mode−locked cw laser. A new mode of gate operation is demonstrated in which incremental transmission is linearly proportional to pump power. Direct temporal measurement of a 2.1−psec response time of the optical Kerr effect in CS2is reported.

ISSN:0003-6951    

DOI:10.1063/1.88092

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Previous charge−centroid studies of MNOS devices have shown that electrons injected into the insulator structure from the silicon are trapped not solely at the dielectric interface, but can be distributed over nearly the entire nitride thickness. In this paper, results of charge−centroid measurements on thin−oxide MNOS devices are interpreted with a charge trapping model, leading to values for the nitride trap density, capture cross section, and average trapping distance of 6×1018/cm3, 5×10−13cm2, and 35 A˚, respectively.

ISSN:0003-6951    

DOI:10.1063/1.88093

出版商:AIP    

年代:1975

数据来源: AIP