摘要:

It is shown that for surface wave delay lines with parallelepiped substrate geometry, the plate modes of the substrate describe the entirety of the spurious responses of the transducers. Experimental evidence is presented which shows that by carrying out a superposition of the plate modes, both the in‐band distortion and the out‐of‐band rejection can be quantitatively predicted.

ISSN:0003-6951    

DOI:10.1063/1.1655234

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

It is shown that well‐characterizedFandMcenters can be introduced into NaF crystals by both additive and electrolytic coloring techniques. This success is attributed primarily to a substantial elimination of hydroxyl‐ion contamination.

ISSN:0003-6951    

DOI:10.1063/1.1655235

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

It is shown that the principal characteristic feature of the surface acoustic waves in piezoelectrics—the presence of an alternating electric field transverse to the surface, which can be of the same order of magnitude as the longitudinal field—may not only give rise to the known transverse acoustoelectric effect but also lead to amplification of surface acoustic waves by electron drift perpendicular to the surface. For Love waves in a piezoelectric semiconductor film on a highly conducting substrate, the amplification coefficient is found and the conditions necessary for amplification are investigated.

ISSN:0003-6951    

DOI:10.1063/1.1655236

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Spectral measurements of light scattered at various angles from a laser‐produced plasma were made at the laser frequency &ohgr;L, and at &ohgr;L/2, 3&ohgr;L/2, 2&ohgr;L, 5&ohgr;L/2, and 3&ohgr;Lusing a mode‐locked Nd:glass laser to produce intensities of 1016W/cm2at the target. Signals were detected at &ohgr;L, 3&ohgr;L/2, and 2&ohgr;L, and their intensities relative to the incident intensity were determined. Upper bounds were set for the intensities at the other frequencies.

ISSN:0003-6951    

DOI:10.1063/1.1655237

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Holographic microinterferometry is applied to the study of laser‐produced plasmas. A 150‐psec 1.06‐&mgr;m light pulse from a neodymium laser is used for both production and diagnostics of the plasma. An interferogram, obtained 0.5 nsec after irradiation by a 1/2‐J pulse, is presented. It is pointed out that spatial resolution is limited by plasma motion during passage of the 100‐psec frequency‐doubled diagnostic pulse.

ISSN:0003-6951    

DOI:10.1063/1.1655238

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

The spectral character of the optical absorption produced by ionizing radiation in several fibers and fiber materials has been measured. The nature of the damage has been identified in some of the samples and preliminary work has been successful in synthesizing radiation‐protected soda lime silicate glasses for fiber applications.

ISSN:0003-6951    

DOI:10.1063/1.1655239

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

The response to ionizing radiation of a suite of high‐purity silicas, a titanium‐doped silica, high‐purity germania, and silica fibers with germanium‐doped and titanium‐doped cores has been measured. The radiation sensitivity of these materials was found to depend upon the atmosphere used during a heat treatment prior to irradiation.

ISSN:0003-6951    

DOI:10.1063/1.1655240

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

A new type of green‐light‐emitting negative‐resistance gallium phosphide diode has been produced by diffusing ap‐njunction into a singlen‐type liquid epitaxy growth. This growth includes a narrow high‐resistivity layer introduced by the transient incorporation of deep acceptors. The negative resistance has been shown to be due to optical feedback between the emitting junction and the photosensitive high‐resistivity region. External quantum efficiencies of 0.08% at 565 nm with a current density of 11 A cm−2have been obtained from these devices when used in a true latching mode with a standing bias of 5 V and turn‐on turn‐off pulses of ±4 V.

ISSN:0003-6951    

DOI:10.1063/1.1655241

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Superlattice structures made by molecular beam epitaxy are profiled by a combined technique of argon sputter etching and Auger electron spectroscopy. The superlattice, consisting of periodic layers of 50‐Å GaAs and Ga1−xAlxAs, probably represents the structure with the shortest period ever made and analyzed in monocrystalline semiconductors. Also established is the dependence of the intensity ratio of aluminum to arsenic signals of Auger transitions on the aluminum composition in Ga1−xAlxAs.

ISSN:0003-6951    

DOI:10.1063/1.1655242

出版商:AIP    

年代:1974

数据来源: AIP

摘要:

Charge stored in an insulating layer on a semiconductor can influence the field at the surface of the semiconductor and consequently control the surface recombination velocity. This paper describes the use of this effect to control the current in a reverse‐biasedp‐njunction in the semiconductor. When an electron beam is used to write and read the stored charge, the effect can be used to produce high‐resolution high‐gain devices that have a variety of potential uses in information‐storage applications. Experiments demonstrating this effect are described.

ISSN:0003-6951    

DOI:10.1063/1.1655243

出版商:AIP    

年代:1974

数据来源: AIP