摘要:

From measurements of shifts in the resonant frequency of SAW resonators, it has been observed that the SAW propagation velocity under an interdigital transducer varies continuously as a function of external resistive or capacitive loads. For Al onYZLiNbO3at 34 MHz, the velocity under a transducer can be varied over a 1.4% range. Resonators, using a transducer to control the cavity transit time, have been fabricated which are continuously tunable up to 60 kHz. Capacitances are found to be superior as tuning elements, owing to the severe degradation of the resonance caused by resistances.

ISSN:0003-6951    

DOI:10.1063/1.88564

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Results are reported on the production of 400‐keV 50‐nsec‐duration 1.3‐kA deuteron beams using a reflex triode.

ISSN:0003-6951    

DOI:10.1063/1.88559

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

We have made a theoretical investigation of the emission process for the (111)AandBfaces of GaAs activated to negative electron affinity taking into account the full Bloch nature of the wave function of the photoexcited electron. We find that, within the abrupt‐step model for the potential in the surface region, the emission probability is sensitive to the amount of band bending in the space‐charge region. We also find that, all other things being equal (magnitude of the negative electron affinity, amount of band bending, etc.), the emission probability for theBface is considerably higher than that for theAface.

ISSN:0003-6951    

DOI:10.1063/1.88572

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Boron ions with energy ranging from 40 to 250 kev have been implanted at room temperature in type‐IIadiamonds with doses of 1015and 1016cm−2. The boron profiles have been measured using an ion analyzer. These profiles are compared with profiles calculated using Winterbon’s theory. Reasonable agreement between experimental and theoretical profiles is obtained for the electronic stopping cross section measured by Omrodetal. up to about 180 keV.

ISSN:0003-6951    

DOI:10.1063/1.88573

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Silicon crystals have been implanted at room temperature with 3.2×1015ions/cm2of 300‐keV N+. The spatial distribution of displaced atoms has been determined by the backscattering energy spectra as a function of the crystal tilting angle with respect to the ⟨111⟩ axis. The changes in the extracted depth profiles have been correlated to the nonuniform distribution of defects across the channel. The radial distribution of displaced atoms has been determined on the basis of the flux‐peaking treatment for impurity lattice location.

ISSN:0003-6951    

DOI:10.1063/1.88574

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

The stimulated Raman gain of theQbranch of the first vibrational transition of atmospheric N2was measured with a nonfocused primary‐laser single‐pass amplifier configuration. The Raman signal which was amplified over a path of 8.53 m was provided by a near‐ir dye laser pumped by the ruby primary laser. The Raman cross section was determined from the measured gain.

ISSN:0003-6951    

DOI:10.1063/1.88560

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

In the measurement of hydroxyl (OH) concentrations in air using the technique of resonance fluorescence, it was established that the presence of ambient ozone led to significant interference. It is concluded that this is a result of OH formation due to laser‐induced dissociation of ozone. A reduction in the power density of excitation was required to reduce this effect to a negligible level.

ISSN:0003-6951    

DOI:10.1063/1.88561

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

This paper applies a novel stabilization technique to the effective glow discharge excitation of uv nitrogen lasers at gas pressures ranging from 0 to 5 bar. The plasma is produced between uniform field electrodes and can be stabilized at electrode separations of down to 1 mm. The stabilization is relatively insensitive to the electrode geometry and surface finish. Megawatt pulses were obtained from a 25‐cm atmospheric‐pressure device energized by a simple flat‐plate Blumlein circuit.

ISSN:0003-6951    

DOI:10.1063/1.88562

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Double‐heterostructure GaAs1−xSbx/AlyGa1−yAs1−xSbx@qLinjection lasers have been operated continuously at room temperature for the first time. Emission was near 1.0 &mgr;m. The lowest threshold current density observed was 2.1 kA  cm−2dc.

ISSN:0003-6951    

DOI:10.1063/1.88563

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Photoconductivity produced by picosecond optical pulses in silicon has been used to switch electrical signals as large as 1.5 kV. The signals have been used to drive a traveling‐wave Pockel’s cell for efficient optical switching with a measured rise time of approximately 25 psec.

ISSN:0003-6951    

DOI:10.1063/1.88565

出版商:AIP    

年代:1976

数据来源: AIP