bluuebunny/crossref_metadata_2025 huggingface dataset:
TEMPERATURE TUNING OF AN ORGANIC DYE LASER
Authors: Schappert Gottfried T. , Billman Kenneth W. , Burnham David C.
Published: January 2004

The wavelength spectrum of an organic dye laser (DTTC in ethanol) pumped by a Q-switched ruby laser has been measured as a function of temperature (−117°C to +78°C) for several dye concentrations. Absorption and fluorescence spectra were also obtained. The results are in qualitative agreement with the model of a vibrationally broadened two-level system, each of which is separately thermalized.
DIRECT OBSERVATION OF ACOUSTOELECTRIC DOMAINS
Authors: Moore A. R.
Published: January 2004

By combining optical strain-birefringence with stroboscopic illumination, acoustoelectric domains in CdS have been made visible. Domain widths of 50 to 200 μ have been observed in crystals with drift field perpendicular to the C axis. In crystals with E parallel to C axis the domain travels at 30° with respect to C and forms a complex reflection pattern.
CO2 LASER RADIATION ABSORPTION IN SEMI-INSULATING GALLIUM ARSENIDE
Authors: Klein C. A. , Rudko R. I.
Published: January 2004

In conjunction with studies relating to high-power CO2 laser windows the linear absorption coefficient α of Cr-doped GaAs was measured by means of calorimetric techniques. It was found that α ≈ 0.02 cm−1, at room temperature. This result is shown to be consistent with theoretical considerations: At 10.6 μ, the lattice absorption of GaAs stems from the existence of a fourth-order electric moment and does not involve the fundamental resonance.
A DYE-SOLUTION LASER PUMPED BY A DYE LASER
Authors: Yamaguchi Gentaro , Murakawa Shin-ichi , Yamanaka Chiyoe
Published: January 2004

The wavelength shift phenomena of a dye laser and a dye laser oscillation pumped by another dye laser were studied by introducing two dye cells in a cavity. Simultaneous laser oscillations at different wavelength ranges were obtained, and a 4-level laser mechanism of the dye laser system is discussed.
EFFICIENT GREEN ELECTROLUMINESCENCE IN NITROGEN-DOPED GaP p-n JUNCTIONS
Authors: Logan R. A. , White H. G. , Wiegmann W.
Published: January 2004

P–N junctions have been formed in GaP using the liquid-phase epitaxy process. In addition to the shallow donors and acceptors, nitrogen has been added to the grown layer to increase η, the room-temperature external quantum efficiency of the electroluminescence of the green emitting A line and its phonon replicas. The measured value of η was as high as 0.1% dc and 0.2% pulsed. The nonradiative processes are reduced by using sulfur rather than other shallow donors to fabricate the n side of the junction.
FERROELECTRIC Sr1−xBaxNb2O6 AS A FAST AND SENSITIVE DETECTOR OF INFRARED RADIATION
Authors: Glass A. M.
Published: January 2004

It has been found that ferroelectric Sr1−xBaxNb2O6 has a very large pyroelectric coefficient at room temperature for 0.25 < x < 0.5. This suggested that the material may be useful as a detector of infrared radiation. A detector, constructed with a value of x=0.33 was successfully used at 300°K to detect single pulses of 10.6-μ radiation from a Q-switched CO2 laser with a rise time of less than 30 nsec. Detectors with a low frequency responsivity of better than 104 V/W and a minimum detectable power of 4 × 10−9 W-cm−1-cps−1/2 are easily constructed. Methods of improving on these results are discussed.
ALPHA-IODIC ACID: A SOLUTION-GROWN CRYSTAL WITH A HIGH FIGURE OF MERIT FOR ACOUSTO-OPTIC DEVICE APPLICATIONS
Authors: Pinnow D. A. , Dixon R. W.
Published: January 2004

The photoelastic properties of α-HIO3 have been measured and the applicability of the material for acousto-optic device applications determined. In the blue and green portions of the visible the material has the highest figure of merit, n6p2/ρv3, of any known crystal, approximately twelve times that of LiNbO3 and fifty times that of fused silica. Other desirable properties for these applications include (a) the availability of large solution-grown single crystals of high optical quality, (b) low acoustic and optic losses, and (c) the absence of ``optical damage.''

A simple acoustically driver beam deflector was also constructed to demonstrate the potential of this material. It was found that 70% of a 0.63-μ laser beam could be deflected, over a bandwidth of 55 MHz, with an electrical drive power of 265 mW, while 70% of a 0.488-μ laser beam could be deflected over the same bandwidth with 94 mW of electrical power.
FRANZ-KELDYSH EFFECT WITH GUNN DOMAINS IN BULK GaAs
Authors: Guetin P. , Boccon-Gibod D.
Published: January 2004

Optical modulation near the intrinsic edge is observed in bulk n-type GaAs using the Gunn effect at room temperature. A possible mechanism involves a shift of the absorption edge by the high electric field of propagating domains (Franz-Keldysh effect). We also report some results on the production of extra carriers by photon-initiated excitation which provides a means of changing the conductivity profile and current waveform of Gunn oscillators.
TRANSIENT DOUBLE INJECTION IN GERMANIUM
Authors: Dean R. H.
Published: January 2004

Some new features of the step-voltage transient behavior of an electron-hole plasma injected via contacts into a long bar of p-type germanium are observed and explained theoretically. When the leading edge of the propagating plasma reaches the anode there is a cusp in the time derivative of the current, and thereafter the current increases with time essentially as constant x[1 - exp (−t/τ)], where τ is the recombination time.
THE ACCURACY OF THE WKB APPROXIMATION FOR TUNNELING IN METAL-SEMICONDUCTOR JUNCTIONS
Authors: Padovani F. A. , Stratton R.
Published: January 2004

Detailed numerical analysis indicates that the density of states factor, previously predicted to occur for the exact transmission probability, only applies for carrier energies of a few meV. This casts doubt on the method used by Conley to derive the density of states in degenerate semiconductors.
EFFICIENT CW LASER OSCILLATION AT 4416 Å IN Cd (II)
Authors: Silfvast W. T.
Published: January 2004

A gain of 20%/m and a power output of 50 mW have been measured on the 5s2 2D5/2 → 5p2P03/2 4416-Å laser transition in Cd (II) using a single isotope of Cd114. The system was operated in a tubular furnace at temperatures in the range of 200°C with He as a buffer gas. The laser output with respect to He pressure, discharge current, and furnace temperature are discussed along with a proposed excitation mechanism. The system appears to have the prospect of being one of the most efficient, high power lasers operating in the visible region of the spectrum.
OBSERVATION OF MODE LOCKING AND ULTRASHORT OPTICAL PULSES INDUCED BY ANTISOTROPIC MOLECULAR LIQUIDS
Authors: Comly J. , Garmire E. , Laussade J. P. , Yariv A.
Published: January 2004

Mode locking and ultrashort pulses have been produced in a giant-pulse ruby laser with heated nitrobenzene (T > 110°C) or α-chloronaphthalene (T > 62°C) inside the optical resonator. 10−11-sec pulses were observed with the two-photon fluorescence technique.
PHOTOCONDUCTIVITY IN SINGLE-CRYSTAL Pb1−xSnx Te
Authors: Melngailis I. , Harman T. C.
Published: January 2004

Photoconductivity at wavelengths up to 15 μ at 77°K and up to 20 μ at 4.2°K has been observed in Bridgman-grown and subsequently annealed crystals of Pb1−xSnx Te which had carrier concentrations ranging from 2 to 8 × 1015 cm−3 with a mobility of about 3 × 104 cm2/V-sec at 77°K. Detectivity values generally were between 108 and 109 cm/W-sec1/2 at 77°K and greater than 1010 cm/W-sec1/2 at 4.2°K. Photoconductive lifetimes of about 10−8 at 77°K and higher temperatures and 10−6 sec at 4.2°K were measured by means of light pulses from a GaAs diode laser.
OPTIMIZATION OF AUGER ELECTRON SPECTROSCOPY IN LEED SYSTEMS
Authors: Palmberg P. W
Published: January 2004

The sensitivity and resolution of Auger electron spectroscopy in a display-type LEED system have been optimized by incorporation of a high-current grazing incidence gun and addition of a fourth grid to the standard three-grid system.
MODE-LOCKING OF CW LASERS BY REGENERATIVE RF FEEDBACK
Authors: Huggett G. R.
Published: January 2004

Dynamic mode locking of a He–Ne laser was accomplished by detecting the rf beats between axial modes, and by using this signal as external regenerative feedback to the laser, making the system a self-oscillator at the axial mode difference frequency of 75 MHz. The feedback signal was applied to the laser by means of a KD*P longitudinal modulator placed in the laser cavity to provide phase modulation. The average output power of the laser was 50 mW; the peak pulse power was about 1.25 W.
STIMULATED RAMAN GAIN COEFFICIENTS FOR Li6NbO3, Ba2NaNb5O15, AND OTHER MATERIALS
Authors: Johnston W. D. , Kaminow I. P. , Bergman J. G.
Published: January 2004

The available gain for stimulated Raman scattering has been computed from measured values of absolute spontaneous Raman scattering cross sections at 300° and 80°K for various materials including Li6NbO3 and Ba2NaNb5O15. The power gain coefficients and power required for 1% gain per pass with confocal geometry at λ = 1.065 μ are tabulated for the more promising materials. Operation of a CW or quasi-CW Raman oscillator appears feasible, particularly with the most efficient material, Li6NbO3.
CURRENT PUSHING OF THE OSCILLATION FREQUENCY OF A 6328-Å He–Ne LASER
Authors: Arrathoon R. , Siegman A. E.
Published: January 2004

Increasing the discharge current through a small dc-excited 6328-Å laser changes the index of refraction of the discharge and causes a blue shift of the laser oscillation frequency of ∼1 MHz/mA. The shift is independent of laser cavity tuning and decreases with increasing dc discharge current. Approximate calculations plus other experiments indicate that this shift represents the dispersive effects of the strong 6334-Å and 6402-Å upward transitions from the neon 1s5 metastable level. The residual spectral width and FM noise in stable 6328-Å lasers, especially as compared to 1.15-μ lasers, may be due to plasma disturbances acting through this dispersive mechanism, rather than to microphonic disturbances as commonly suggested.
THE ELECTRICAL BEHAVIOR OF IMPLANTED BISMUTH IN SILICON
Authors: Marsh O. J. , Baron R. , Shifrin G. A. , Mayer J. W.
Published: January 2004

The electrical behavior of 20–50-keV Bi implanted layers in silicon has been evaluated using Hall effect and sheet resistivity measurements. Implants of greater than 1014/cm2 performed at room temperature show a large increase in the number of carriers/cm2 for short anneals at ≈600°C that is associated with the reordering of the lattice. Although Rutherford scattering measurements (performed at Chalk River Nuclear Laboratories) indicate that ≈80% of the Bi atoms are substitutional, only ≈20% are effective electrically. The peak value of the carrier density distribution is ten times the corresponding maximum solid solubility.
LASER-PRODUCED SPARKS IN A 200-kG MAGNETIC FIELD
Authors: Chan P. W. , DeMichelis C. , Kronast B.
Published: January 2004

Laser-produced sparks in air, butane, and helium at atmospheric pressure have been studied in a 200-kG magnetic field. The influence of the magnetic field on the breakdown threshold, on the visible radiation emitted by the plasma, and on the plasma expansion has been investigated.
CRITICAL CURRENT DENSITIES IN SUPERCONDUCTING NIOBIUM FILMS SPUTTERED REACTIVELY IN THE PRESENCE OF NITROGEN GAS
Authors: Muto Y. , Koto N. , Fukuroi T. , Saito Y. , Anayama T. , Mitsuoka T. , Onodera Y.
Published: January 2004

A critical current density of about 2 × 105 A/cm2 in a transverse external field of 73 kOe, parallel to the film plane, was obtained at liquid-helium temperature for niobium films deposited on glass substrates by sputtering technique in an argon atmosphere with a dilute addition of nitrogen. This critical current density is larger than any other reported values for refractory metal carbides and nitrides with the NaCl structure.
SIZE EFFECT IN THIN SINGLE-CRYSTAL SILVER FILMS
Authors: Duggal V. P. , Nagpal V. P.
Published: January 2004

A discrepancy has been observed between the experimental behavior of electrical resistivity and temperature coefficient of resistivity as a function of film thickness in thin single-crystal silver films when compared with geometrical size effect theory. The discrepancy has been attributed to the observed change in the microstructure of the films as shown by the transmission electron microscopy study and to the effect of lattice as well as electron energy quantization on electrical conduction. The study calls for an exact calculation of the role of quantization in structurally perfect thin films.
ELECTROLUMINESCENCE OF RARE-EARTH AND TRANSITION METAL MOLECULES IN II-VI COMPOUNDS VIA IMPACT EXCITATION
Authors: Kahng D.
Published: January 2004

It is shown experimentally that it is possible to excite rare-earth and transition metal ions included in a II-VI compound matrix as fluoride molecules by direct, hot-electron impact. Electron-hole pairs in the matrix are unnecessary and even undesirable. AC excitation of a thin film structure has given external power conversion efficiency of about 10−4 at several optical frequencies including the 5480-Å line of Tb3+.
SILICON SURFACE STRUCTURE
Authors: Broudy R. M. , Abbink H. C.
Published: January 2004

Experimental results are reported and interpreted which are consistent with the hypothesis that the Si(111) 7 × 7 LEED pattern is associated with the presence of an impurity of low-volume solubility, such as Fe.
SCANNING ELECTRON BEAM DISPLAY OF DISLOCATION SPACE CHARGE
Authors: Mataré H. F. , Laakso C. W.
Published: January 2004

Germanium and silicon monocrystals with controlled grown-in medium-angle grain boundaries and crystals with isolated dislocations are subjected to a scanning electron beam (SEB) with simultaneous application of a bias field in a transversal direction. Amplification of the induced current signals and oscillographic display reveals clearly the extended space charge of defects and the junction behavior of a two-dimensional array of edge dislocations with a radius of the space-charge pipe from a few microns to 25 microns.
TUNNELING IN METAL-GLASS-SILICON STRUCTURES
Authors: Laibowitz Robert B.
Published: January 2004

Low-temperature conductance peaks have been observed in tunneling measurements on aluminum-phosphosilicate glass-degenerate silicon sandwich structures. In magnetic fields up to 84 kOe these peaks split and, with certain assumptions, the g value for the impurity responsible for the peak is found to be 2.1 ± 0.1.
HOLOGRAPHIC STORAGE IN LITHIUM NIOBATE
Authors: Chen F. S. , LaMacchia J. T. , Fraser D. B.
Published: January 2004

Single-crystal lithium niobate has been used as a holographic storage medium. The material undergoes a change in refractive indices upon exposure to suitably intense light thus allowing it to act as a pure-phase, volume-holographic medium requiring no processing. The holograms formed have high diffraction efficiencies and are thermally erasable. The high resolution obtained suggests that such material may be useful in high-capacity, changeable optical information storage, processing and display devices.
PHENOMENOLOGICAL TREATMENT OF SMALL-SCALE LIGHT TRAPPING
Authors: Piekara Arkadiusz H.
Published: January 2004

The calculation of filament diameter is based on the wave equation involving field-dependent electric permittivity for light frequencies expanded up to sixth power of electric field vector. With reasonable assumptions a diameter of 4–6 μ has been obtained. For increasing power fed into the beam two or more filaments may be formed simultaneously. It is believed that there exist relaxation processes inside the filament somewhat diminishing nonlinear terms of electric permittivity. Thus, the solution of the wave equation becomes divergent resulting in filament vanishing. As a result, new filaments occur sequentially, forming an apparent light channel.
MECHANISM OF IONIC CONDUCTION AT HIGH FIELDS
Authors: Dell'Oca C. J. , Young L.
Published: January 2004

Capacitance measurements have been used to distinguish between the effective field and ionic avalanche models for the autocatalytic buildup of ionic current on applying a constant high field to tantalum pentoxide films.
SELECTION AND AMPLIFICATION OF A SINGLE MODE-LOCKED OPTICAL PULSE
Authors: Kachen G. , Steinmetz L. , Kysilka J.
Published: January 2004

A single pulse was selected from the train of mode-locked pulses of a Nd-glass laser using optics external to the oscillator cavity. Its pulse width was measured by the two-photon fluorescence technique to be 10 to 15 psec with and without amplification. From energy measurements, the amplified single-pulse power was determined to be typically 30 GW.
ELECTRON EMISSION FROM THE SCHOTTKY BARRIER STRUCTURE ZnS:Pt:Cs
Authors: Williams R. , Wronski C. R.
Published: January 2004

Emission of electrons into vacuum from a forward-biased Schottky barrier has been demonstrated experimentally. The emitting contact is a thin layer of platinum on n-type conducting ZnS with the outer surface of the platinum cesiated to reduce its work function. Capacitance and photoemission measurements indicate that the ZnS:Pt barrier height is 2.3 eV. Under forward-bias emission is observed.
SIMULTANEOUS PHASE-LOCKING OF LONGITUDINAL AND TRANSVERSE LASER MODES
Authors: Smith P. W.
Published: January 2004

By using a discharge tube filled with pure neon as a nonlinear element, it has been found possible to obtain simultaneous locking of both longitudinal and transverse modes of a 6328 Å He–Ne laser. Under certain circumstances, each transverse mode has all its longitudinal resonances phase locked to form a narrow pulse, but the pulses corresponding to the various transverse mode orders do not coincide in time. Beam scanning has been observed when the frequency spacing between the transverse modes is a simple fraction of the longitudinal mode spacing. Under these conditions, a ``spot'' of light traces out a zig-zag path in the laser cavity.
EVIDENCE AGAINST LASER-INDUCED SPONTANEOUS ELECTRON EMISSION FROM REAR SIDE OF METAL FOILS
Authors: Li P. W. , Isenor N. R.
Published: January 2004

Evidence is given that the reported prompt emission of electrons from the rear side of Q-switched laser-illuminated metal foils does not occur. The effect has been eliminated by careful light shielding of the electron collector.
EFFICIENT, HIGH RESOLUTION, PHASE DIFFRACTION GRATINGS
Authors: Shankoff T. A. , Curran R. K.
Published: January 2004

Experiments on the sodium D lines and an 0.82-Å separated doublet in the iron spectrum have shown that holographically recorded dichromated gelatin diffraction gratings have resolving powers within 90% of theory. The diffraction gratings are of excellent optical quality, have background scatter less than 10−4 of the signal, are ghost free and have greater than 90% first-order diffraction efficiency. Blazing is accomplished by rotating the grating to the incident angle which satisfies the Bragg condition for the blaze wavelength. The 3-μ-thick transmission gratings can be employed from 0.25 μ to at least 15 μ, with gelatin absorption interfering only at 2.6–4.0 μ and 5.8–8.5 μ.
EVIDENCE FOR SINUSOIDAL PHASE MODULATION IN SMALL SELF-TRAPPED FILAMENTS
Authors: Lifsitz J. R. , Grieneisen H. P. H.
Published: January 2004

Evidence is presented indicating that, in some cases at least, a sinusoidal phase modulation is responsible for the spectral broadening observed in trapped filaments of laser (and Raman) light. This kind of modulation has been suggested recently by Cheung et al.
FREEZE-OUT CHARACTERISTICS OF THE MOS VARACTOR
Authors: Gray Peter V. , Brown Dale M.
Published: January 2004

Experimental MOS C(V) data are obtained in the temperature range over which majority carriers are substantially frozen out (40° − 70°K). These are compared with calculated curves and other calculated curves are presented to show the effect of impurity concentration and compensation. The C(V) curves are characterized by a secondary minimum in capacitance near the flat band bias.
MAGNETIC FIELD MEASUREMENTS IN THE SCANNING ELECTRON MICROSCOPE
Authors: Thornley R. F. M. , Hutchison J. D.
Published: January 2004

The scanning electron microscope has been used to obtain quantitative values for the fields and field gradients emerging from magnetic heads or tapes. The microscope is used to image a known reference detail adjacent to the field source and the fields are computed from the resultant pattern distortion. Gradients are obtained by measuring the resultant astigmatism of the scanning beam. Fields down to 10 Oe were measured from a tape recorded at 100 cycles/cm.
RELAXATION PHENOMENA IN THE WATER VAPOR LASER
Authors: Jeffers W. Q. , Coleman P. D.
Published: January 2004

Relaxation behavior of 17 water vapor laser lines in the range 23- to 79-μ wavelength, obtained with a split-discharge laser, is presented. Two discharges are incorporated in the same laser resonator and pulsed at varying times. The laser signal produced by the first discharge then probes the decaying second discharge at subsequent time intervals. Measuring the absorption as a function of time permits one to measure relaxation rates and suggests processes going on at different times. A fall out of this work is some new gain measurements on the 27.97- and 118.59-μ lines.
CO2 LASER-INDUCED ELECTRON EMISSION FROM METALS
Authors: Duley W. W.
Published: January 2004

Thermionic emission from molybdenum and tungsten targets irradiated with a cw CO2 laser beam has been observed. The incident energy is ≃ 0.2–0.5 J per pulse at a repetition rate of 120 cps. Peak electron currents are 0.1 mA.
THREE-PHOTON PHOTOELECTRIC EFFECT IN K3Sb
Authors: Shiga Fuminori , Imamura Shunji
Published: January 2004

Cubic response in photoelectric emission from K3Sb illuminated by a Nd-glass laser was investigated. Comparison of energy distribution of emitted electrons under the laser irradiation and monochromatic irradiation of natural light (3000–3500 Å) showed that most of the photoelectrons excited by simultaneous absorption of three laser photons were changed in energy distribution by collision with valence electrons.
HYDROGEN MOLECULAR VACUUM ULTRAVIOLET LASER THEORY
Authors: Ali A. W. , Kolb A. C.
Published: January 2004

Calculations indicate that within the Werner band of the H2 molecules laser action is possible at several spectral lines between 1025–1239 Å in a high current discharge with a risetime of a few nsec. The peak power densities are in the kilowatts cm−3 range per spectral line (for strong lines) with pulse half-width of less than 1 nsec.
THERMOLUMINESCENCE AND PARAMAGNETIC HOLE CENTERS IN BaF2
Authors: Tzalmona A. , Pershan P. S.
Published: January 2004

Thermoluminescence of rare-earth doped BaF2, irradiated with x rays at 77°K, is interpreted in terms of the appearance and disappearance of three paramagnetic hole centers. One of the centers is associated with an interstitial fluorine.
FLUX-DEPENDENT ASPECTS OF THE EVOLUTION OF ACOUSTOELECTRIC DOMAINS IN n-GaAs
Authors: Spears David L. , Bray Ralph
Published: January 2004

Optical probe studies of propagating acoustoelectric domains in n-GaAs reveal a self-narrowing of the domain during growth, and an apparent limitation to the peak acoustic density in the domain, illustrating the role of flux-dependent processes in domain evolution. A mechanism is discussed, based on evidence for changes in spectral composition of the domain at high acoustic intensity.
LOW-TEMPERATURE EPITAXIAL GROWTH OF PN JUNCTIONS BY UHV SUBLIMATION
Authors: Thomas R. N. , Francombe M. H.
Published: January 2004

The feasibility of growing epitaxial pn junctions at temperatures as low as 550°C by sublimation in UHV has been demonstrated. The junctions, which show abrupt impurity profiles, have excellent and predictable rectification characteristics. Transmission electron microscope studies suggest good crystallographic perfection. The relatively high minority carrier lifetime of 6 μsec which was measured indicates a low concentration of lifetime killing impurities at the junction region.
ELECTRON BEAM MODULATED REFLECTANCE OF GERMANIUM
Authors: McCoy John H. , Wittry David B.
Published: January 2004

A technique for modulation of the reflectance of germanium in the 2–3-eV range by means of a periodically gated electron beam is described. The relative reflectance curves resemble the thermoreflectance results, but the amplitude varies with the one-third power of the excess carrier density. The results agree with a theory that at large excess carrier densities the mean distance between carriers is small enough to cause a modification of the crystal potential and therefore to lower critical point transition energies.
PHOTOEMISSION OF ELECTRONS AND HOLES INTO SILICON NITRIDE
Authors: Goodman Alvin M.
Published: January 2004

The photoemission of both electrons and holes from degenerate silicon into thin (160–270 Å) layers of silicon nitride has been observed. The threshold energies for these processes are found to be 3.17 ± 0.1 eV for electrons and 3.06 ± 0.1 eV for holes. In addition, the photoemission of electrons from aluminum into silicon nitride has been observed; the threshold energy in this case is 2.11 ± 0.1 eV. An approximate electron energy band diagram for silicon nitride based on these values is presented.
INTERPRETATION OF THE PERIODICITY IN ENERGY LOSS OF A WELL-CHANNELED ION WITH RESPECT TO ITS NUCLEAR CHARGE
Authors: Harrison Don E.
Published: January 2004

The Z1 periodicity in the inelastic energy loss cross section is shown to be contained in the electron density of the moving ions when that density is determined from Hartree—Fock—Slater wavefunctions.
THE DYNAMIC RESPONSE OF SOLIDS EXPOSED TO A PULSED-ELECTRON-BEAM
Authors: Oswald R. B. , Schallhorn D. R. , Eisen H. A. , McLean F. B.
Published: January 2004

The first measurements of free surface displacement and velocity induced by the absorption of a pulse of electrons in a solid are reported. The laser-interferometric measurements demonstrate that the dynamic response of materials induced by charged particle interaction can be observed in detail.
LASER INDUCED UNDERWATER SPARKS
Authors: Barnes Peter A. , Rieckhoff K. E.
Published: January 2004

Measurements have been taken of the radiative flux density, the spectrum, and the temporal behavior of laser induced underwater sparks. When a 30-MW Q-switched ruby laser was focused into water, the resulting spark revealed a blackbody-like spectrum with a temperature of 15 000°K. The spark was delayed in time by 15 nsec with respect to the laser pulse and had a temporal behavior very similar to the laser pulse producing it.
VACUUM DEPOSITION OF AlN ACOUSTIC TRANSDUCERS
Authors: Wauk M. T. , Winslow D. K.
Published: January 2004

Thin-film microwave acoustic transducers of piezoelectric aluminum nitride (AlN) have been vacuum deposited by two methods. Aluminum nitride was deposited on metallic film substrates at 300°–1200°C by evaporating aluminum in the presence of either nitrogen gas dissociated in an ac discharge or in the presence of ammonia gas. Longitudinal ultrasonic waves were generated in a sapphire rod with a one-way-tuned conversion loss of 10 dB at 1700 MHz.
DOPANT DEPENDENCY OF FERMI LEVEL LOCATION IN HEAVILY DOPED SILICON
Authors: Tao T. F. , Hsia Yukun
Published: January 2004

Results obtained from the study of the incremental conductance of metal to heavily doped n-type Si barrier tunneling as a function of bias voltage are presented. The Si is variously doped with P, As, and Sb. Experimental data indicate that the location of Fermi level is strongly dependent on dopant types.
THE PRESENCE OF DEEP LEVELS IN ION IMPLANTED JUNCTIONS
Authors: Hunsperger R. G. , Marsh O. J. , Mead C. A.
Published: January 2004

It has been found that ion implantation doping results in the generation and diffusion of defect species, forming deep trapping levels. The effect of these levels on the electrical characteristics of zinc-implanted GaAs diodes has been observed for the case of 70-kV implantation at 400°C into substrates with n-type concentrations ranging from 1 × 1016 to 1.8 × 1018 atoms/cm3. Capacitance-voltage measurements have indicated the presence of a semi-insulating layer in the diodes, varying in thickness from 0.18 μ for the most heavily doped substrate to 2.7 μ for the lightest. Frequency dependence of the junction capacitance and power law variation of forward current vs voltage have also been observed and are attributed to deep levels.
SELF-LOCKING OF THREE MODES IN THE He–Ne LASER
Authors: Jones D. G. C.
Published: January 2004

An approximate criterion for the self-locking of three laser modes is developed from Lamb theory and tested against experiment.
NEW HIGH-POWER STABLE MODES OF OPERATION OF THE ARGON LASER
Authors: Yarborough J. M. , Hobart J. L.
Published: January 2004

We report several new high-power stable modes of operation of the argon laser. These types of operation are characteristic of the laser itself; no mode-selecting techniques are used. We have observed output powers of 2 W with up to 90% of the power in a single optical frequency, as well as several other new stable output spectra.
MEASUREMENT OF SOUND VELOCITIES IN CRYSTALS USING BRAGG DIFFRACTION OF LIGHT AND APPLICATIONS TO LANTHANUM FLUORIDE
Authors: Krischer Charles
Published: January 2004

A method of measuring sound velocities in crystals using Bragg diffraction of light by ultrasonic waves is described. Sound-velocity data presented for LaF3 are consistent with a trigonal crystal structure and exclude the possibility of a hexagonal structure.
HIGH-PERFORMANCE LITHIUM NIOBATE ACOUSTIC SURFACE WAVE TRANSDUCERS AND DELAY LINES
Authors: Collins J. H. , Gerard H. M. , Shaw H. J.
Published: January 2004

Radiation resistance measurements have been made on 20 electrode pair interdigital transducers deposited on poled crystals of lithium niobate, for a variety of cuts and propagation directions, with the objective of determining optimum geometries for the efficient wideband generation of acoustic Rayleigh waves. Using Y cut, Z axis propagating lithium niobate and five-electrode pair transducers a 100-MHz delay line has been constructed with an insertion loss of 11.5 dB at a delay of 8.9 μsec, and a −3-dB bandwidth of 24 MHz.
AMPLIFICATION OF ACOUSTIC SURFACE WAVES WITH ADJACENT SEMICONDUCTOR AND PIEZOELECTRIC CRYSTALS
Authors: Collins J. H. , Lakin K. M. , Quate C. F. , Shaw H. J.
Published: January 2004

Strong interaction between the wave on the surface of a piezoelectric crystal and the wave on the drifting carriers in a nearby semiconductor is reported. Amplification can result and two-port net terminal gain of 7 dB at 108 MHz with a delay of 9 μsec has been observed.
CO2 LASER LINEWIDTH BY MEASUREMENT OF STEP RESPONSE
Authors: Bridges T. J. , Haus H. A. , Hoff P. W.
Published: January 2004

Fast rise pulses from a GaAs electrooptic switch are used to measure the small signal time response to a step of radiation, of a 20 dB, homogeneously broadened CO2, He, N2 laser amplifier. By comparing the observed shape of the time response (rise time ≈ 15 nsec) with theory, the value of T2, the homogeneous relaxation time, and hence the linewidth is obtained as a function of gas pressure. The doppler broadening (59 MHz), pressure broadening (4.67 MHz/Torr) and gas temperature (372°K) are obtained.
PHOTOCHROMIC CHANGE IN REFRACTIVE INDEX
Authors: Hammer J. M.
Published: January 2004

Light-induced changes in the refractive index of transition metal doped SrTiO3 has been observed. This is the first observation of photochromic index of refraction changes. The measurements are made by observing the variation of transmission of a Fabry-Perot cavity made of the material studied. Changes in the index of refraction of 1–5 × 10−5 per unit change in optical density per centimeter are found. These values agree reasonably well with values calculated from the measured absorption curves.
EVIDENCE FOR DIRECTIONAL COUPLING BETWEEN SEMICONDUCTOR CARRIERS AND SLOW CIRCUIT WAVES
Authors: Sumi Masao , Suzuki Toshimasa
Published: January 2004

An experiment on the interaction between drifting carriers in semiconductors and slow electromagnetic waves in external circuit was performed. Carriers in n-type InSb were coupled with slow waves through meander-type and helix-type circuits at 77°K. Measurements of transmitted microwave power through these systems give clear evidence for directional coupling by this sort of interaction.
ELECTRIC-FIELD-INDUCED SHIFT OF THE INTERFERENCE PEAKS OF THIN TANTALUM OXIDE FILMS
Authors: Frova A. , Migliorato P.
Published: January 2004

The electric-field-induced shift to higher energies of the interference peaks of thin tantalum oxide films was observed. The effect has been described in terms of a quadratic electro-optic coefficient g12 which shows a dispersion when the region of absorption is approached.
COMPRESSION OF PULSES FROM A MODE-LOCKED He–Ne LASER
Authors: Duguay M. A. , Hansen J. W.
Published: January 2004

Pulses of 500-psec duration, emitted by a mode-locked He–Ne laser, have been electro-optically frequency swept and then compressed to 270 psec by multiple reflections from an interferometer proposed by Gires and Tournois.
STUDY OF INHOMOGENEITIES IN GaAs USING A SCANNING ELECTRON MICROSCOPE
Authors: McAvoy B. R. , Green D. , Ing D. W. , Ure R. W.
Published: January 2004

A scanning electron microscope was used to observe the bulk electrovoltaic effect in GaAs devices. Displays showing the distribution of inhomogeneities of carrier concentration over an area of a sample of bulk or epitaxial GaAs were produced. A correlation was found between the device performance and the inhomogeneity distribution observed in the material.
CURRENT CONTROLLED NEGATIVE DIFFERENTIAL RESISTIVITY OF P-TYPE TELLURIUM
Authors: Nimtz Günter , Seeger Karlheinz
Published: January 2004

Current-voltage measurements made with p-type tellurium at 77°K are reported. Voltage pulses sufficiently short to avoid the formation of electroacoustic domains were applied to the sample. The small deviations from Ohm's law at low current densities are interpreted by polar optical mode scattering and scattering by lattice defects. At a field strength of 3 kV/cm there is a region of negative differential resistivity in the transition to current densities an order of magnitude larger. A change in effective mass by intervalley transition of hot holes is discussed.
TIME AVERAGE HOLOGRAPHY EXTENDED
Authors: Aleksoff C. C.
Published: January 2004

It is demonstrated that the usefulness of time-average holography in analyzing vibration can be extended by modulating the reference beam.
ANOMALOUS ELECTRICAL PROPERTIES OF SOLUTION-GROWN, P-TYPE GaP
Authors: Foster L. M. , Woods J. F. , Lewis J. E.
Published: January 2004

The hole concentration determined from Hall effect measurements on Zn-doped, solution-grown GaP was found to exceed the Zn concentration. It has not been established whether the effect is due to additional acceptor defects introduced simultaneously with the Zn, or to an anomalously small Hall mobility/drift mobility ratio.
A THEORETICAL EXPLANATION OF THE LOW-FIELD MICROWAVE EMISSION FROM InSb
Authors: Harth W. , Jaenicke R.
Published: January 2004

A theory is presented for the microwave emission from n-InSb at 77°K in the presence of magnetic and low electric fields using Maxwellian electron velocity distribution and piezoelectric coupling between sound and plasma waves. The case of crossed fields is discussed in detail. Magnetoresistance effect and Doppler-shifted acoustic cyclotron resonance are the essential mechanisms which determine the magnetic field dependence of the microwave emission.
INVESTIGATION OF LOW POWER LASER SIGNALS WITH PICOSECOND RESOLUTION
Authors: Gloge D. , Roldan R.
Published: January 2004

A device is described that employs second harmonic generation to analyze the output from low-power lasers. It consists of a calcite beam splitter and a KDP second-harmonic generator. Its high sensitivity and resolution are demonstrated by investigating the output from several free-running cw GaAs lasers.
FOUR-PHOTON OPTICAL PARAMETRIC NOISE IN WATER
Authors: Weinberg Donald L.
Published: January 2004

Optical parametric noise has been produced in a centrosymmetric medium, water, by a 9-MW ruby laser beam. The wavelengths, in the visible, and the angles of emission agree with the tuning curve calculated for a phase-matched four-photon process. A power of ≈½μW emitted into a 38-Å band is observed in the low-loss wavelength range, in approximate agreement with theory. Very strong idler absorption has little apparent effect on the signal power or bandwidth.
PIEZOELECTRIC PROPERTIES OF Ba2 NaNb5 O15
Authors: Warner A. W. , Coquin G. A. , Meitzler A. H. , Fink J. L.
Published: January 2004

Single-crystal Ba2NaNb5O15 (z plate) has been found to have a piezoelectric coupling factor in the thickness longitudinal mode kt equal to 0.57. As a value of kt determined by direct measurement, this result is the highest value yet reported for a single-crystal ferroelectric material usable at and above room temperature. Since this material has good mechanical handling characteristics, a relatively low dielectric constant (ε33S/ε0 = 30), and a pure mode of vibration, plates of this material are attractive for applications as high-frequency longitudinal mode transducers. The approximate values of the thickness shear mode coupling factors for x and y plates are k15 = 0.20 and k24 = 0.20.
PRODUCTION OF FAST JETS OF IONIZED BARIUM USING EXPLOSIVE SHAPED CHARGES
Authors: Hunter J. , Martelli G. , Martin K. S. , Rothwell P.
Published: January 2004

Barium jets have been produced in a series of preliminary ground tests using the shaped-charge technique; this suggests that ionized barium metal streams may be injected in this way into the ionosphere with the object of measuring ionospheric electric fields.
EXCITATION OF ACOUSTIC WAVES IN A CO2 DISCHARGE PLASMA
Authors: Exner V. L. , Pekárek L.
Published: January 2004

A relatively slight voltage pulse disturbance produces an acoustic wave in a CO2 dc discharge. The amplitude is so large that indirect indication by means of changed light intensity in the column is possible. An explanation of high efficiency of excitation is proposed in terms of dissociation of CO2 molecules.
AN IRRADIATION EFFECT IN THERMALLY GROWN SiO2
Authors: Wells Oliver C.
Published: January 2004

Thermally grown silicon dioxide layers were irradiated with kilovolt electrons, and the equilibrium surface potential was measured by passing the secondary electrons through an energy analyser. The incident electrons at 5-keV energy penetrate for 3300 Å into a 5700-Å oxide film. The observed equilibrium surface potential is initially less than 1 V which indicates efficient induced conductivity; but after 10 C/cm2 it is −30 V (which indicates that the conductivity has diminished); and finally at 20 C/cm2 it is less than 1 V again. Annealing reverses the process. A model is proposed.
TEMPERATURE DEPENDENCE OF LATTICE DISORDER CREATED IN Si BY 40 keV Sb IONS
Authors: Picraux S. T. , Westmoreland J. E. , Mayer J. W. , Hart R. R. , Marsh O. J.
Published: January 2004

The temperature dependence of lattice disorder created in Si by 40-keV Sb ions was studied by energy analysis of the yield of backscattered 1-MeV He ions incident along 〈111〉 and 〈110〉 axes. Doses of ∼ 1 × 1013 Sb ions/cm2 were used so that the disorder level was below that representing an amorphous layer. The disorder per incident ion decreases strongly with implant temperature above 50°C. This is approximately 100°C lower than the region of corresponding decrease in the anneal of a low-dose room-temperature implantation. For implantation temperatures less than 50°C, the disorder per ion was only mildly temperature-dependent.
GENERATION OF COHERENT ULTRASONIC WAVES WITH GaAs GUNN OSCILLATOR
Authors: Hayakawa H. , Ishiguro T. , Mikoshiba N. , Kikuchi M.
Published: January 2004

The experimental success in the generation of coherent ultrasonic waves from a GaAs Gunn oscillator with a dc pulse is reported. The frequency of the ultrasound is independent of the mechanical eigenfrequency of the oscillator.
ELECTRON BEAM CHANNELING IN SINGLE-CRYSTAL SILICON BY SCANNING ELECTRON MICROSCOPY
Authors: Wolf E. D. , Everhart T. E.
Published: January 2004

An annular semiconductor diode detector was used in a Cambridge Stereoscan electron microscope to resolve beam-orientation-dependent backscattered electron images not only as bands but also as extremely complicated defect and excess line patterns with angular resolution ≤ 5 × 10−4 rad. The resultant patterns are similar in appearance to transmission and reflection Kikuchi electron diffraction patterns.
TEMPERATURE AND FREQUENCY DEPENDENCE OF MICROWAVE ELASTIC LOSSES IN β-RHOMBOHEDRAL BORON FOR LONGITUDINAL WAVES ALONG THE c AXIS
Authors: Young J. D. , Oliver D. W. , Slack G. A.
Published: January 2004

The frequency dependence of microwave elastic losses for longitudinal waves along the c axis of a β-rhombohedral boron crystal have been measured from 0.5 to 1.8 GHz at 4 and 300°K. At 1 and 1.5 GHz, the temperature dependence of these losses has been determined from 4 to 300°K. At 300°K, the attenuation due to interaction with thermal phonons is found to vary quadratically with frequency, in accord with theory, and to have a value of 0.1 dB/cm at 1 GHz. The sound velocity of the longitudinal wave along the c axis is found to be 1.4 × 106 cm/sec.
THE INFLUENCE OF WEAK rf FIELDS ON SCINTILLATION RISE TIMES
Authors: Short A. M. , Dance J. B.
Published: January 2004

Various organic scintillators have been placed in rf fields. The light emitted during the first few nanoseconds of the fluorescence may be greatly reduced if the frequency of the rf is about 340 MHz. rf stimulation shapes fluorescence pulses and this may be used to eliminate noise and enhance neutron-γ separation in a scintillation detector.
OPTICAL SECOND- AND THIRD-HARMONIC GENERATION IN CHOLESTERYL NONANOATE LIQUID CRYSTAL
Authors: Goldberg Lawrence S. , Scnnur Joel M.
Published: January 2004

Laser-induced generation of second- and third-harmonic radiation is studied in cholesteryl nonanoate and in other cholesteric and nematic liquid crystals. No second harmonic is observed in any of the liquid-crystal mesomorphic phases, indicating their ordered molecular arrangements to be centrosymmetric. Large changes in third-harmonic intensity occur at several phase transitions, and their possible origins are considered.
A NEW NEGATIVE MAGNETO-RESISTANCE EFFECT IN GERMANIUM
Authors: Newhouse V. L. , Furgason E. S. , Ellis T. D.
Published: January 2004

A decrease in resistivity with increasing magnetic field has been found in high-purity n-type germanium subjected to crossed E and B fields at 4.2°K. The effect is due to an increase in carrier density with increasing B caused by impact ionization of previously un-ionized donors, and is associated with the presence of the Hall electric field. It is accompanied by bulk oscillations in the megacycle range.
CONDUCTIVITY AND HALL MOBILITY OF ION-IMPLANTED SILICON IN SEMI-INSULATING GALLIUM ARSENIDE
Authors: Sansbury James D. , Gibbons James F.
Published: January 2004

Chromium-doped semi-insulating gallium arsenide has been successfully doped n-type by ion implantation of silicon. Annealing studies are presented which show that at annealing temperatures in excess of 600°C, conductivity and Hall mobility rise to values comparable to those expected for heavily doped gallium arsenide.
ANNEALING CHARACTERISTICS OF n-TYPE DOPANTS IN ION-IMPLANTED SILICON
Authors: Crowder B. L. , Morehead F. F.
Published: January 2004

Investigations of the conditions under which the donors, P, As, and Sb, are incorporated into Si by by ion implantation (260–300 keV) in an electrically active form are reported. Above a critical dose, room-temperature implantations followed by a 600°C post anneal are substantially more effective than implantations at 600°C.
INTERNAL FLUX MOTION IN LARGE JOSEPHSON JUNCTIONS
Authors: Scott A. C. , Johnson W. J.
Published: January 2004

A ``displaced linear branch'' has been observed in the volt-ampere characteristics of square (1 × 1-mm) Sn–Ox–Sn and Pb–Ox–Pb Josephson junctions. The slope of the linear branch is independent of magnetic field and independent of temperature below 2.2°K. It is suggested that this effect can be attributed to internal flux motion.
AVALANCHE SHOCK FRONTS IN p-n JUNCTIONS
Authors: Bartelink D. J. , Scharfetter D. L.
Published: January 2004

A new transient mode of avalanche breakdown in p-n junctions is described. For sufficiently high current, a region of impact ionization of carriers advances as a shock front whose velocity can be several times faster than the carrier-saturated drift velocity. Since the passing disturbance rapidly fills the depletion region with a dense plasma of holes and electrons, it has been used to interpret the observed high-efficiency microwave oscillations of the trapped-plasma ``TRAPATT'' mode. An approximate analysis is given, and compared with numerical calculations.
PARAMETRIC EXCITATION AND QUENCHING OF LONGITUDINAL PLASMA WAVES
Authors: Hasegawa Akira , Davidson R. , Goldman R.
Published: January 2004

General conditions of parametric excitation and parametric quenching of the longitudinal plasma waves involving negative energy wave(s) are derived by expressing the growth rate of these waves in terms of quantities involving only the linear plasma conductivities and the amplitude of density modulation by the pump.
DIRECT EVIDENCE OF DIVACANCY FORMATION IN SILICON BY ION IMPLANTATION
Authors: Stein H. J. , Vook F. L. , Borders J. A.
Published: January 2004

The production of divacancies in Si by 400-keV oxygen ion implantation (ΦI = 1.75 × 1014 cm−2, two sides) was detected by the characteristic divacancy optical absorption band at 1.8 μ. This band has been previously correlated with the presence of divacancies in electron- and neutron-irradiated silicon. Ion-produced divacancy annealing near 200°C was observed to correlate with neutron-produced divacancy annealing. Detailed comparisons of the annealing of electron-, neutron-, and ion-produced divacancies suggest that the ion-produced divacancies anneal primarily in regions with sink concentrations ≥ 1019 cm−3.
TWO-STREAM INSTABILITIES IN A SEMICONDUCTOR IN THE PRESENCE OF A MAGNETIC FIELD
Authors: Guéret P.
Published: January 2004

Carrier wave instabilities in semiconductors having only one type of carriers (electrons) are described. These instabilities are shown to result from a nonuniformity in the electron drift velocity, and to occur only in the presence of a magnetic field. It is also shown that the mechanism that is responsible for the instability is the same whether the magnetic field be transverse or parallel to the direction of electron drift.
TEMPERATURE AND COMPOSITIONAL DEPENDENCE OF LASER EMISSION IN Pb1−xSnxSe
Authors: Harman T. C. , Calawa A. R. , Melngailis I. , Dimmock J. O.
Published: January 2004

Laser emission has been obtained in Pb1−xSnxSe diodes with x up to 0.28, and the temperature dependence of the emission has been studied in the range from 1.5 to 100°K. The results strongly support a band model in which the conduction and valence band edge states cross as the Sn content is increased from 0 to 0.28. For x ≤ 0.10, the temperature coefficient of the energy gap is positive whereas for x ≥ 0.19, the temperature coefficient is negative as predicted by the band model. Also, the results provide evidence that the energy gap is direct on both sides of the crossover point which at 4.2°K occurs for x ≈ 0.15.
SUBMICROSECOND HOLOGRAPHIC CINE-INTERFEROMETRY OF TRANSMISSION OBJECTS
Authors: Jahoda F. C.
Published: January 2004

The method of ``live-fringe'' holographic interferometry has been adapted for use on transmission objects with two ruby lasers replacing the customary cw laser. The hologram is produced with a giant pulse laser and reconstructed with another laser having a pulse width of 50 μsec. Consecutive, real time interferograms can be obtained during this period with image converter cameras pulsed on for as little as 0.1-μsec intervals.