• Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

1 Dec 1968

Volume 13, Issue 11, pp. 365-397


EVOLUTION OF A Q‐SWITCHED LASER PULSE FROM NOISE

J. A. Fleck

Appl. Phys. Lett. 13, 365 (1968); http://dx.doi.org/10.1063/1.1652473 (3 pages) | Cited 11 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
Q‐switched laser emission is calculated using a fluctuating dipole model of spontaneous emission. The emission pattern for a broadband noise source is a complicated quasi‐periodic train of short pulses.

SATURATED ABSORPTION BY NEON INSIDE A 6328 Å LASER WITH A MIXTURE OF NEON ISOTOPES IN ITS GAIN TUBE

Walter G. Schweitzer

Appl. Phys. Lett. 13, 367 (1968); http://dx.doi.org/10.1063/1.1652474 (2 pages) | Cited 3 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
In a saturated absorption experiment with neon in a 6328‐Å He☒Ne laser one can select a combination of isotopes of neon in the gain tube and the proper isotope in the loss tube so as to bring the maximum of the gain curve to the same frequency as that of the saturated absorption peak.

INTERFEROMETRIC OBSERVATION OF ABSORPTION INDUCED INDEX CHANGE ASSOCIATED WITH THERMAL BLOOMING

E. A. McLean, Louis Sica, and A. J. Glass

Appl. Phys. Lett. 13, 369 (1968); http://dx.doi.org/10.1063/1.1652475 (3 pages) | Cited 11 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
The induced index changes associated with thermal blooming have been observed in iodine‐doped CCl4 by means of a Mach‐Zehnder interferometer. The interference fringe shape next to the window and the temporal growth of the peak fringe displacement at various positions in the cell have been analyzed. Both the conductive and convective stages of thermal blooming are observed.

OPTICAL SATURATION IN LASER LIGHT SCATTERING

Stanislaw Kielich

Appl. Phys. Lett. 13, 371 (1968); http://dx.doi.org/10.1063/1.1652476 (3 pages) | Cited 6 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
Possibilities of observing light scattering from an intense laser beam, whose electric field in well‐defined conditions can cause total orientation of the scattering microsystems, are investigated on the basis of a simple classical theory. This saturation of orientation affects the scattered light and should be accessible to measurement in solutions of macromolecules or colloidal particles by usual laser technique, whereas in molecular liquids it cannot be made apparent even if using the focused beam of a strong laser. The measurements under consideration are proposed as a novel and simple method of determining the sign of the optical anisotropy of macromolecules and colloidal particles.

SINGLE‐MODE POWER FROM A 6328 Å LASER INCORPORATING NEON ABSORPTION

Paul H. Lee, Peter B. Schoefer, and W. Benjamin Barker

Appl. Phys. Lett. 13, 373 (1968); http://dx.doi.org/10.1063/1.1652477 (3 pages) | Cited 33 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
Strong mode‐coupling was induced in a long 6328‐Å He☒Ne laser by the addition of a separate cell containing excited Ne. The resulting single‐frequency output power represented most of the total multimode power available. The laser maintained the same mode of oscillation when tuned throughout the entire gain band. This scheme has produced 9.5 mV at a single frequency and was apparently free from any inherent power limitation.

EFFECTS OF RADIATION PRESSURE ON A LASER‐PRODUCED PLASMA

Hugo Weichel, C. D. David, and P. V. Avizonis

Appl. Phys. Lett. 13, 376 (1968); http://dx.doi.org/10.1063/1.1652478 (4 pages) | Cited 3 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
Four specific experimentally observed phenomena associated with a laser‐produced carbon plasma in a vacuum are described. They are superheating of the target surface, a sharply defined and slightly indented leading boundary of the expanding plume, a density precursor in the expanding plume, and the merging of the electron and ion temperatures at very high laser fluxes. These observations are explained in terms of the effects of the laser beam's radiation pressure on the otherwise freely expanding plasma. The radiation pressure for a typical 10‐J Q‐switched ruby laser pulse with a half width of 65 nsec is equivalent to a maximum of 10 atm of pressure when focused to a 1‐mm‐diam spot.

LATTICE LOCATION OF DOPANT ELEMENTS IMPLANTED INTO Ge

K. Björkqvist, B. Domeij, L. Eriksson, G. Fladda, A. Fontell, and J. W. Mayer

Appl. Phys. Lett. 13, 379 (1968); http://dx.doi.org/10.1063/1.1652479 (3 pages) | Cited 16 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
The orientation dependence of the backscattered yield of 1.8‐MeV carbon ions has been used to determine the lattice location of In, Tl, Sb, Bi, and Pb ions implanted into Ge at 30–40 keV and at temperatures between 300° and 350°C. Similar to the behavior in silicon, the group IV and V elements are found to be highly substitutional. Thallium exhibits nearly equal numbers of atoms in the 〈111〉 interstitial sites and on the substitutional sites (as in Si). In indium implants, on the other hand, we find no evidence of the clearly defined interstitial component previously seen in Si. In all cases, we observe substitutional concentrations orders of magnitude above thermal equilibrium solubilities.

PREFERRED ORIENTATION IN BIAS‐SPUTTERED NICKEL CHROMIUM FILMS

E. Stern and T. B. Light

Appl. Phys. Lett. 13, 381 (1968); http://dx.doi.org/10.1063/1.1652480 (4 pages) | Cited 5 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
It is shown that substrate bias during dc sputtering effectively reduces oxygen contamination in nichrome films. This in turn leads to an enhancement of the preferred orientation of the deposits. Moreover, it appears that substrate bias plays an additional role in film orientation which is related to the initial nucleation and growth conditions.

PULSE BROADENING IN A MHD COPPER VAPOR LASER

J. F. Asmus and N. K. Moncur

Appl. Phys. Lett. 13, 384 (1968); http://dx.doi.org/10.1063/1.1652481 (2 pages) | Cited 12 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
Stimulated emission has been observed from an electrically accelerated copper plasma at 5106 and 5782 Å in a device employing a series of plasma guns which inject the vapor into the laser resonator. In addition to facilitating room temperature operation of a copper laser, this technique provides a flowing active medium which has extended the pulse duration by more than four‐fold over that originating from a stationary vapor.

STIMULATED EMISSION FROM CdS AT ULTRA‐HIGH CURRENT DENSITY ELECTRON BEAM PUMPING

J. L. Brewster

Appl. Phys. Lett. 13, 385 (1968); http://dx.doi.org/10.1063/1.1652482 (3 pages) | Cited 7 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
Stimulated emission to 3 × 108 W∕cm3 (about 200‐kW peak) have been obtained from CdS platelets, using a 3‐nsec, 260‐keV electron accelerator. Data are reported from 20 to 1400 A∕cm2 at 300°K, and 500 A∕cm2 at 77°K showing approximately constant efficiency at points well above threshold.

X‐RAY DIFFRACTION TOPOGRAPHY WITH A VIDICON TELEVISION IMAGE SYSTEM

Jun‐ichi Chikawa and Isao Fujimoto

Appl. Phys. Lett. 13, 387 (1968); http://dx.doi.org/10.1063/1.1652483 (3 pages) | Cited 25 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
Reproduction of x‐ray diffraction topographic images has been made at about 25 diameters enlargement by a closed‐circuit television camera system with an x‐ray sensing Vidicon tube which utilizes a beryllium window and PbO photoconductive target. The height of video signals is exactly proportional to x‐ray intensity, and intensity distribution can be observed as a video waveform. It is shown that the television image system can be used for rapid observations of topographic images such as Pendellösung fringes and imperfections in crystals, although its resolution (about 30 μ) is inferior to that of the photographic method.

A Nb TM010 MODE CAVITY WITH HIGH ELECTRIC FIELD AND Q0

Ira Weissman and J. P. Turneaure

Appl. Phys. Lett. 13, 390 (1968); http://dx.doi.org/10.1063/1.1652484 (2 pages) | Cited 7 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
A superconducting Nb TM010 mode cavity at 8.5 GHz machined from a single piece of reactor‐grade electron‐beam‐melted Nb to avoid joints had an unloaded Q (Q0) of 2 × 1010. After some degradation in the Q0, which took place as the microwave fields were increased, a high Q0 of 1 × 109 was obtained at a peak electric field on the cavity surface of 27 MV∕m. These results were obtained by using ultrahigh‐vacuum firing and chemical polishing of the Nb cavity, and ultrahigh vacuum within the cavity during measurement. The high Q0 at high electric field demonstrates the usefulness of superconducting Nb cavities for devices such as linear particle accelerators and rf separators.

PHOTOSENSITIVE BARIUM TITANATE SCHOTTKY DIODES

David E. Sawyer

Appl. Phys. Lett. 13, 392 (1968); http://dx.doi.org/10.1063/1.1652485 (2 pages) | Cited 3 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
The observation of photocurrents generated in Schottky barrier diodes on Remeika‐grown reduced barium titanate is reported. Photon‐to‐electron conversion efficiencies of 5% at 0.3 μm have been measured which suggests that the effect may be large enough for employment in practical devices.

RESPONSE OF THERMALLY SOFTENED DEFECT STRUCTURES IN ALLOYS TO AN APPLIED STRESS

J. C. Erdmann and J. A. Jahoda

Appl. Phys. Lett. 13, 393 (1968); http://dx.doi.org/10.1063/1.1652486 (3 pages) | Cited 4 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
Alloy specimens, after predeformation at 4.2°K and intermittent holding at higher temperatures, respond to reapplication of stress by transient evolution of heat. These heat bursts have been measured and are interpreted as due to the breakdown of unstable defect configurations.

EFFICIENT CW SECOND HARMONIC GENERATION TO 2573 Å

M. W. Dowley

Appl. Phys. Lett. 13, 395 (1968); http://dx.doi.org/10.1063/1.1652487 (3 pages) | Cited 9 times

Online Publication Date: 17 October 2003

Full Text: | Download PDF

Show Abstract
Efficient cw second harmonic conversion to 2573 Å has been achieved in an argon laser cavity by means of the nonlinear materials ADP and KDP. Peak SH power was 415 mW which represented 50% efficiency. Trace impurities in the crystals prevented the realization of theoretical efficiency. An increase in cavity loss was observed during the simultaneous presence of fundamental and SH beams.
Close
Google Calendar
ADVERTISEMENT

close