摘要:

LiTaO3pyroelectric detectors have been fabricated in a novel complementary domain configuration that reduces the interference from vibrational noise sources and from changes in ambient temperature by over an order of magnitude relative to the performance of conventional pyroelectric detectors. Detectors made in this complementary domain configuration exhibitD’s in excess of 109cm Hz1/2 W−1, and the measuredD’s degrade less than 10% in the presence of accelerations as great as 0.05gin a 1‐Hz bandwidth, or temperature changes of 10 °C/min.

ISSN:0003-6951    

DOI:10.1063/1.88343

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

The wavelength dependence of the peak transverse acoustoelectric voltage and the surface acoustic wave attenuation determine the energy band and the locations of the surface states in the energy gap of GaAs. The dependence is explained by direct optical transition between the bands and optical transition from surface states. This method needs no contacts to the semiconductor surface, is simple, very sensitive, and accurate.

ISSN:0003-6951    

DOI:10.1063/1.88344

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

The interface between Si and thermally grown SiO2has been examined in detail by low‐energy4He+ion scattering. The oxide composition is shown to be stoichiometric to within 15–20 A˚ of the interface. ISS depth profiles clearly establish a region of excess Si that extends from the interface into the oxide for 15–20 A˚, corresponding to four or five molecular layers. The amount of excess Si is calculated from the experimental data as 1.4×1014atoms/cm2per monomolecular layer (about 20% excess).

ISSN:0003-6951    

DOI:10.1063/1.88345

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

X‐ray photoelectron spectra of colored WO3films, thermodynamic analysis of galvanic behavior of the tungstic oxide cathode, plus other new lines of evidence, clearly establish the previously uncertain mechanism of the electro‐optic effect in amorphous WO3, viz., a simultaneous injection of electrons and positive ions into a film via an electrochemical process, with the consequent development of a low‐xtungsten bronze. The positive ion, in both the films and in tungsten bronzes, remains fully ionized even in the presence of high densities of injected electrons.

ISSN:0003-6951    

DOI:10.1063/1.88346

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

A recent paper bases several conclusions regarding electronic and nuclear stopping powers of silicon for implanted boron on a few capacitance‐voltage measurements of impurity profiles. We suggest here that the accuracy ofC‐Vdata is insufficient to distinguish small changes in projected range, and that measurements with better resolution are required.

ISSN:0003-6951    

DOI:10.1063/1.88347

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

A transverse‐flow mixing HF/DF laser transition was frequency stabilized to better than 500 kHz relative to the second harmonic of a CO laser using a heterodyne technique. An absolute frequency of 110 725 697.4±7 MHz was measured for the 1‐OP(6) line of the HF laser, which represents a factor of 100 improvement in accuracy over existing data.

ISSN:0003-6951    

DOI:10.1063/1.88348

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Double‐heterojunction AlxGa1−xAs lasers have been prepared with a compositional discontinuity &Dgr;xat the heterojunctions of 0.45–0.68 and active region widths of ∼0.1 &mgr;m. These devices have the lowest room‐temperature threshold current densities (475 A/cm2) yet reported, with a differential quantum efficiency of 40% or more.

ISSN:0003-6951    

DOI:10.1063/1.88351

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

A luminescence band at 770 nm due to iron centers has been observed in lithium niobate crystals treated at 520 °C in lithium carbonate. Without this treatment only a broad background luminescence was observed. The main effect of the treatment is to reduce iron centers to the Fe2+state but some evidence was found that destruction of shallow traps is also involved in increasing the luminescence.

ISSN:0003-6951    

DOI:10.1063/1.88352

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

A steady‐state nonequilibrium population distribution of the vibrational states of carbon monoxide has been produced by optical pumping. A supersonic flow CO laser was used to excite a flowing mixture of CO which is pressure broadened by argon. A V‐V pumped nonequilibrium distribution was measured over the first 30 vibrational states of CO.

ISSN:0003-6951    

DOI:10.1063/1.88326

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

The power of a cw water‐vapor laser operating on the far‐infrared transitions of 118.6 and 220 &mgr;m has been considerably improved by the use of helium and hydrogen gas additives. The laser power on the 118.6‐&mgr;m transition has been increased by an order of magnitude from 1.5 to 15 mW in a nonoptimized cavity. For the same discharge current of 1.8 A, the power on the 220‐&mgr;m line has been increased from 0.26 to 1.3 mW.

ISSN:0003-6951    

DOI:10.1063/1.88327

出版商:AIP    

年代:1975

数据来源: AIP