Showing papers on "Ruby laser published in 1978"
TL;DR: In this article, the properties of boron-implanted silicon annealed by high power Q-switched ruby laser radiation are compared with results obtained by conventional thermal annealing.
Abstract: The properties of boron‐implanted silicon annealed by high‐power Q‐switched ruby laser radiation are compared with results obtained by conventional thermal annealing. Laser annealing of the implanted layer results in significantly increased electrical activity, as compared to thermally annealed implanted silicon. This correlates well with transmission electron microscopy and ion‐channeling measurements which show a dramatic removal of displacement damage as a result of laser annealing. A substantial redistribution of the implanted boron concentration profile occurs after laser annealing which cannot be explained by thermal diffusion in the solid.
196 citations
TL;DR: In this paper, the time evolution of temperature and melting in amorphous silicon layers laser irradiated was calculated numerically, and a good agreement was found between the experimental As profiles after laser irradiation and those calculated with a diffusion coefficient of 10−4 cm2/s for As in liquid silicon.
Abstract: The time evolution of temperature and melting in amorphous silicon layers laser irradiated was calculated numerically. Experiments were performed in Si crystals implanted with 400‐keV As to a dose of 5×1015/cm2 and illuminated with 50‐ns‐duration Q‐switched ruby laser pulse in the energy range 1.0–3.0 J/cm2. Comparison between experimental and calculated results allows a quantitative understanding of the amorphous–to–single‐crystal transition. A good agreement was found between the experimental As profiles after laser irradiation and those calculated with a diffusion coefficient of 10−4 cm2/s for As in liquid silicon.
112 citations
TL;DR: In this paper, the redistribution of B, P, As, and Sb profiles was studied by secondary ion mass spectrometry and ion backscattering and the altered profiles were in good agreement with theoretical calculations to be presented in a subsequent paper which show that redistribution occurs as a result of diffusion in the molten state.
Abstract: The redistribution of B, P, As, and Sb implanted into single‐crystal silicon and subsequently laser annealed with a Q‐switched ruby laser has been studied by secondary‐ion mass spectrometry and ion backscattering. Substantial alteration of the as‐implanted profiles occurs, which is pulse‐energy‐density dependent. The altered profiles are in good agreement with theoretical calculations to be presented in a subsequent paper which show that redistribution occurs as a result of diffusion in the molten state.
92 citations
TL;DR: In this article, a single pulse of ruby laser radiation was shown to cause significant regrowth in the amorphous region of heavily ion-implanted GaAs, suggesting essentially complete substitutionality of the Te.
Abstract: A single pulse of ruby laser radiation is shown to cause significant regrowth in the amorphous region of heavily ion‐implanted GaAs. The implanted Te atoms and the host material both show good channeling dips, suggesting essentially complete substitutionality of the Te. There has been only a minor redistribution of the tellurium atoms. The resulting local Te concentration in the laser‐irradiated sample is more than ten times the known maximum solubility of Te in GaAs.
68 citations
TL;DR: In this article, the incorporation of a pulsed ruby laser into an electronic speckle pattern interferometer was described for observing vibrational and transient events with a double pulsed laser and some typical results were given.
Abstract: This paper describes the incorporation of a pulsed ruby laser into an electronic speckle pattern interferometer. A technique is described for observing vibrational and transient events with a double pulsed laser and some typical results are given. Results of the application of the interferometer to non-destructive testing are included.
65 citations
TL;DR: In this paper, channeling effect techniques with a 2.0 MeV He+ Rutherford backscattering and transmission electron microscopy were used to characterize the crystallized layers after Q-switched ruby laser irradiation of 4000.
Abstract: Channeling effect techniques with a 2.0 MeV He+ Rutherford backscattering and transmission electron microscopy were used to characterize the crystallized layers after Q-switched ruby laser irradiation of 4000 A thick amorphous layer on 〈100〉 and 〈111〉 underlined crystal substrates. At a laser energy density of 2.5 J/cm2 the crystal layer on the 〈111〉 specimen contains a large density of stacking-faults, that on 〈100〉 specimen contains a very small amount of screw dislocation lines. High quality single-crystal layers have been obtained after irradiation at 3.5 J/cm2. From a comparison with the growth rate and defect structure observed in thermally annealed implanted-amorphous layers, we propose that crystal growth by 50 ns pulse laser annealing occurs by melting the amorphous layer.
54 citations
TL;DR: The spectra of plasmas produced by focusing the output of a Q-switched ruby laser on the rare-earth metals have been studied and the use of these continua as simple, reliable background sources for absorption spectroscopy in the vacuum-ultraviolet and soft x-ray region down to 40 A is demonstrated.
Abstract: The spectra of plasmas produced by focusing the output of a Q-switched ruby laser (output 1 J) on the rare-earth metals have been studied From samarium (Z = 62) to ytterbium (Z = 70), strong quasi-uniform continua are emitted in the wavelength range 40–2000 A Line emission from the target elements is absent over most of this wavelength region, particularly below about 600 A The use of these continua as simple, reliable background sources for absorption spectroscopy in the vacuum-ultraviolet and soft x-ray region down to 40 A is demonstrated
46 citations
TL;DR: In this article, the transformation of amorphous Si layers to polycrystalline material induced by Q-switched ruby laser single pulses of 20 and 50 nsec duration has been investigated.
Abstract: The transformation of amorphous Si layers to polycrystalline material induced by Q‐switched ruby laser single pulses of 20 and 50 nsec duration has been investigated. The analysis has been performed by transmission electron microscopy and by channeling measurements using 2.0‐MeV He+ Rutherford backscattering. The average grain size of the polycrystalline layers increases with the incident energy density of the laser pulse in the range 0.6–1.7 J/cm2. A transition to single‐crystal layers is found for incident energy densities around 2.0 J/cm2. The grain size correlates with incident energy density (J/cm2) rather than incident power density (MW/cm2) for these pulse durations.
43 citations
TL;DR: In this paper, the development of an electrical spark in an insulating liquid such as liquid hydrocarbons has been studied using a pulsed laser schlieren technique, which consists of splitting a 15 ns laser pulse, coming from a Q-switched Ruby laser, into two beams one of which is delayed by some 60 ns with respect to the other.
32 citations
TL;DR: In this paper, the amorphous to single crystal transition induced by Q-switched ruby laser pulses has been investigated for Si ion implanted layers of different thickness by the channeling effect with MeV He backscattering and reflection high-energy diffraction.
28 citations
TL;DR: The most prominent feature of Q-switched ruby laser irradiations is their independence of the iris pigment content, whilst the effect of the Nd:YAG laser is much reduced in the absence of pigment, at the energy levels studied.
Abstract: The irides of pigmented and albino rabbits have been irradiated by a) a CW argon laser beam (exposure duration up to 1 s), b) a 1 ms pulses Nd:YAG laser and c) a 30 ns pulses Q-switched ruby laser The immediate and long-term pathologies were analysed by scanning and transmission electron microscopy over a period of 13 months At both the gross and ultrastructural levels, damage configuration may differ considerably, depending on the three modes of irradiation For each source there are both thermal and mechanical damage components and the significance of mechanical effects increases with decreasing pulse duration for a constant pulse energy In the argon experiments, tissue destruction is predominantly a consequence of heat, resulting from conduction and convection The subsequent regeneration of tissue after such heat-induced trauma is fast The effects of the Nd:YAG laser, at the irradiance levels used in the present study, are again predominantly of a thermal nature and are caused by heating and local evaporation The pigmented and the nonpigmented iris epithelium are destroyed and widespread decay of the stroma occurs over some months Such damage never results in full repair The most prominent feature of Q-switched ruby laser irradiations is their independence of the iris pigment content In contrast, at the energy levels studied, the argon laser is entirely ineffective, whilst the effect of the Nd:YAG laser is much reduced in the absence of pigment The consequences of these findings for the clinical applications of such lasers are discussed
TL;DR: In this article, the S 1 → S 0 fluorescence spectrum, between 740 and 940 nm, of azulene solutions (10 −3 M in methanol) excited with a Q-switched ruby laser was presented.
TL;DR: In this paper, a Q-switched ruby laser has been used to anneal GaAs implanted with selenium or tellurium ions, achieving high electrical activity both with and without Si3N4 coatings.
Abstract: A Q-switched ruby laser has been used to anneal GaAs implanted with selenium or tellurium ions. Electron concentrations in the range 1–2 × 1019 cm−3 were measured for samples implanted at room temperature or 200°C with a dose of 1–5 × 1015 ions cm−2. High electrical activities were obtained both with and without Si3N4 coatings.
TL;DR: An apparatus for the measurement of kinetics of small absorption changes (DeltaA approximately 10(-3)-10(-4)) at 820 nm in a biological sample in the nanosecond range after a short high-intensity ruby laser flash is described.
Abstract: An apparatus for the measurement of kinetics of small absorption changes (ΔA≃10−3–10−4) at 820 nm in a biological sample in the nanosecond range after a short high‐intensity ruby laser flash (200 mJ, 8 ns) is described. The laser‐induced fluorescence artefact is greatly reduced by the use of a solid‐state laser diode as source of measuring light, in combination with a microscope lens and a diaphragm. The signal‐to‐noise ratio is enhanced by the use of an avalanche photodetector connected to a laboratory‐made low‐noise and interference‐free amplifier. The signals are processed by a transient digitizer in combination with a signal averager. The response time of the apparatus is about 20 ns. With some modifications the apparatus can be used to measure absorption changes in a broad spectral range.
TL;DR: In this paper, samples of n type GaAs implanted with 1015Zn+/cm2 at room temperature were irradiated with a ruby laser of pulse length 0.8 ms.
Abstract: Samples of n type GaAs implanted with 1015Zn+/cm2 at room temperature were irradiated with a ruby laser of pulse length 0.8 ms. For samples coated with Si3N4 a laser energy of 1.5?2.5 J/cm2 produced electrical activity of 40?50% of the implanted dose. Peak hole concentrations up to about 7 × 1019 cm?3 were measured. Uncoated samples irradiated with similar laser energies were not electrically active.
TL;DR: The quality of the holograms is demonstrated by the reconstructed images taken of laser produced cavitation bubbles following optical breakdown in water.
Abstract: Four holograms are recorded superimposed on the same plate at maximum repetition rates of about 10 kHz. A multiply Q-switched ruby laser produces the series of coherent light pulses for hologram exposure. Image separation of different holograms is achieved by spatial frequency multiplexing. The reference beam direction is altered by a unique acoustooptic beam splitter and deflector unit. The operating principle is a sound pulse-light pulse interception technique. Only one ultrasonic transducer is necessary. The quality of the holograms is demonstrated by the reconstructed images taken of laser produced cavitation bubbles following optical breakdown in water.
TL;DR: In this paper, the results of small-angle ruby-laser Thomson-scattering measurements of the parametric excitation of plasma waves by C${O}}_{2}$laser radiation at quarter-critical density in a laser-heated gas-target plasma were reported.
Abstract: We report the results of small-angle ruby-laser Thomson-scattering measurements of the parametric excitation of plasma waves by C${\mathrm{O}}_{2}$-laser radiation at quarter-critical density in a laser-heated gas-target plasma. From supplementary data obtained from interferometry and large-angle ruby-laser scattering we infer that the threshold conditions for a convective decay are satisfied.
TL;DR: In this paper, the phase conjugate of the incident field is exploited in pulsed laser systems to remove aberrations in the optical train as well as ab-errations arising from turbulence in the atmosphere.
Abstract: This paper deals with certain nonlinear effects that can directly generate a wavefront which is the phase conjugate of the incident field. These phenomena can be exploited in pulsed laser systems to remove aberrations in the optical train as well as ab-errations arising from turbulence in the atmosphere. We discuss our measurements of the effectiveness of this conjugation process using a ruby laser and stimulated Brillouin scattering in a CS2 waveguide device. Measurements are made of the divergence angle of the beam after correction. The application of conjugate processes realizable in SBS, SRS, parametric downconversion, and four-wave mixing is considered for typical CO2 laser systems. System gain, backscatter limitations and parasitic oscillation are discussed for typical pulsed amplifier systems. Amplified spontaneous emission and unwanted glint returns from optical defects appear to be the most serious limitations.
TL;DR: In this article, the authors report the observation of repetitive self-Q-switched pulses from a continuously operating ruby laser pumped by an argon ion laser at a 3 kHz rate.
Abstract: We report the observation of repetitive self‐Q‐switched pulses from a continuously operating ruby laser pumped by an argon ion laser. 500‐W pulses of 2 nsec width at a 3‐kHz rate are observed. It is tentatively concluded from the pulse characteristics and other data that the phenomenon can be explained by a saturable absorber mechanism.
TL;DR: Thermal excitations on a germanium surface under simultaneous irradiation by two monochromatic optical beams, one strong and one weak, are predicted as functions of the angular separation and frequency difference between the beams, their relative polarization, their intensities, and pulse durations.
Abstract: Thermal excitations on a germanium surface under simultaneous irradiation by two monochromatic optical beams, one strong and one weak, are predicted as functions of the angular separation and frequency difference between the beams, their relative polarization, their intensities, and pulse durations. Nonlinear optical reflection for Q-switched ruby laser pulses is then described. Weak reflected and diffracted beam intensities show tendencies in which the former is preferentially enhanced for a downshifted weak beam frequency, while the latter depends only on the shift magnitude. Both are suppressed for large shifts or large angular separations between input beams.
TL;DR: The interaction between a 250 MW CO 2 -laser pulse and a z-pinch plasma during the initial pinch phase has been studied experimentally by means of Thomson scattering of ruby laser light as discussed by the authors.
TL;DR: In this article, the channeling effect with MeV He backscattering was adopted to investigate the structure of the irradiated layer using 50 and 20 ns duration time of the Q-switched laser pulse, and the transition to single crystal for a given material amorphous layer thickness requires nearly the same energy density.
TL;DR: In this paper, the width of a transform-limited pulse obtained at the beginning of the train was 28±2 picoseconds, and at a high output level, rapid deformation arises closer to the peak of a train, resulting in splitting of the pulses into several fragments.
TL;DR: In this article, the design, performance and merits of a ruby laser operating in the unstable-resonator, Q-switched mode are discussed, as well as the performance of the laser.
TL;DR: In this article, a simple method was reported for determining the hardening temperature of a metal by measuring the depths of hardening at different intensities of a pulsed ruby laser.
Abstract: A simple method is reported for determining the hardening temperature of a metal by measuring the depths of hardening at different intensities of a pulsed ruby laser. The value of 834 °C obtained for S45C steel agrees well with the reported value of 850 °C.
TL;DR: Transient stimulated vibrational Raman scattering in liquid HCl, HBr, Cl 2, CO 2, N 2 O, CH 3 F, CH 3 Cl and SF 6 has been observed using a mode-locked ruby laser as discussed by the authors.
TL;DR: A Thomson scattering system has been designed and constructed for probing a relativistic electron beam heated plasma and evidence of the relativistically blue shift was observed.
Abstract: A Thomson scattering system has been designed and constructed for probing a relativistic electron beam heated plasma. Ruby laser light scattered through 90° is resolved by a polychromator and detected by one of six photomultipliers. The system is capable of resolving electron temperatures of 150 eV at densities of ne<1013 cm−3 with a 4‐J ruby laser and an f/9 throughput collection system. Scaling to a 10‐J, f/5 system would allow resolving densities of approximately 1012 cm−3. System design, calibration, alignment, and data reduction are discussed. At elevated temperatures (Te≈600 eV) evidence of the relativistic blue shift was observed.
TL;DR: The intensity-dependent transmission of primary leaves of Triticum aestivum seedlings was measured with single pulses of a Q-switch ruby laser and the result is interpreted as a two-step absorption of cooperative units of 10(5)-10(6) chlorophyll molecules.
TL;DR: In this article, the signal-to-noise ratio (SNR) of ruby laser scattering measurements is studied as a function of the minor radius a, the laser parameters and the characteristics of the detection system.
Abstract: The signal-to-noise ratio (SNR) of ruby laser scattering measurements is studied as a function of the minor radius a, the laser parameters and the characteristics of the detection system. On a tokamak of JET-like dimensions, the SNR will be reduced at least by a factor of 8 with respect to its value on TFR. Possible improvements of present-day scattering devices are discussed.