Electron Beam Pumped Semiconductor Lasers Research Articles

Transport model for a transverse electron beam-pumped semiconductor laser

AbstractA transport model for a transverse electron beam-pumped semiconductor laser has been developed. The model incorporates spatial dependencies of the power deposition from the beam as well as a three-dimensional model of the gain medium and the field intensity of the photons produced by stimulated emission in the oscillation cavity. This model accounts for spatial inhomogeneities and has been solved for a variety of pumping strengths. The model was developed so that it can be benchmarked with electron beam pumping. The dominant mechanisms for the production of electron–hole pair production within the semiconductor material is similar to the dominant mechanisms for the production of electron–hole production using ion beams. Thus, the model can be extended to fission fragment ion pumping of semiconductor lasers in order to model a nuclear-pumped laser/reactor system.

Electron-beam pumped pulsed IR semiconductor laser based on a quantum-size InGaAs/AlGaAs structure

The characteristics of the radiation of a 890-nm laser based on a quantum-size InGaAs/AlGaAs structure, pumped by a (15–26)-keV electron beam, have been studied. An output pulsed power up to 90 W with an efficiency of 3.5% is obtained from each laser end face at room temperature of the active element and a cavity length of 0.5 mm.

High‐efficiency electron‐beam pumped green semiconductor lasers based on multiple CdSe quantum disk sheets

We report on room temperature operation of green electron beam pumped semiconductor lasers based on multiple ZnSe quantum wells with CdSe quantum disk sheets, embedded in the ZnSSe/ZnSe alternately-strained superlattice waveguide. An efficiency of 4% per facet at electron beam energies of 18–21 keV was achieved. The output pulse power up to 12 W was detected. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

ZnSe-Based Room Temperature Low-Threshold Electron-Beam Pumped Semiconductor Laser

We report on room temperature operation of blue-green ZnSe-based electron-beam pumped semiconductor lasers grown by molecular beam epitaxy. The lowest ever reported values of threshold current density in transverse excitation geometry (3-3.5 A/cm 2 ), which is independent of the electron beam energy in the 15-35 kV range, have been obtained. Possible ways to improve the electron-beam pumped laser characteristics are discussed.

Electron-beam-excited lasers based on A2B6 compounds (review)

The literature on electron-beam-pumped semiconductor lasers (EPSLs) based on A2B6 compounds is reviewed. Recent advances in the development of EPSLs in the Nineties are reflected. The literature data on the output parameters of these EPSLs are systematized. Basic parameters and characteristics of EPSLs their hardware realization, the properties of active media, and the mechanisms of amlification and degradation are discussed. The works on the use of EPSLs for pumping of other active media are reviewed.

Optical investigations of short-lived processes using an electron beam pumped semiconductor laser

Optical investigations of short-lived processes using an electron beam pumped semiconductor laser

Microgun pumped semiconductor lasers: Application to CdTe-CdMnTe

We report on a novel ‘microgun pumped semiconductor laser’ (MSL), which is the most compact (few cm 3) electron beam pumped semiconductor laser ever reported. It has been successfully applied to visible laser emission using CdTe/CdMnTe heterostructures, between 90 K–300 K, and also to GaAs/GaAlAs. It operates below 10 kV and below 1 A/cm 2. Since it does not need any doping control or ohmic contact, the MSL should be a viable solution for making compact II–VI lasers in the visible domain.

Full color TV projector based on A 2B 6 electron-beam pumped semiconductor lasers

The description of full color TV projector is given. Three primary colors (red, 620 nm; green, 540 nm; blue, 455 nm) are obtained by means of A 2B 6 e-beam pumped semiconductor lasers. The laser element size is 5 cm. For laser pumping and laser beam controlling, cathode-ray tubes are used. Maximum light output in white is 3000–5000 lm (9–15 W). A full color picture is obtained on a 5 m viewing screen (12 m 2). The size of the laser element is 5 cm. High resolution (up to 2000 pixels per line) gives a possibility to use such a projector in HDTV. The main characteristics of the basic elements are given. It is supposed to begin the development of TV projector with a light output to 10 4 lm.

Spatiotemporal characteristics of laser emission. I

The first chapter describes the general premises of the electrodynamic theory of the laser as a nonstationary nonlinear oscillatory system with spatially distributed parameters. Maxwell's equations are used to derive an equation for the complex amplitude of the electromagnetic field in a cavity filled with transversely inhomogeneous active medium. The self-conssitent analysis includes a simultaneous solution of the equations for the field and for the inverted population. In the second chapter, electrodynamic theory is applied to injection and electron-beampumped semiconductor lasers. The threshold characteristics, the field structure in the near and far zones, the lasing regimes of semiconductor lasers, and the influence of nonlinearity of the refractive index are considered.

Electron-beam-pumped lasers using heteroepitaxial zinc selenide obtained from organoelemental compounds

Investigations were made of the feasibility of using heteroepitaxial ZnSe films grown on GaAs substrates by gas-phase chemical deposition from organoelemental compounds as the active medium of electron-beampumped semiconductor lasers. Studies were made of the characteristics of active elements in transverse and longitudinal excitation geometries and methods of improving them were examined.

The use of electron-beam pumped semiconductor lasers in projection television

The operation of an electron-beam pumped laser as the screen of a television projection tube is described. The relationship among electron-beam current, energy, and beam diameter is discussed.

Application of electron beam pumped semiconductor lasers to projection television

Application of electron beam pumped semiconductor lasers to projection television

Gas plasma gun (GPG) electron-beam pumped semiconductor laser

Gas plasma gun (GPG) electron-beam pumped semiconductor laser

Apparatus for Studying Electron Beam Pumped Semiconductor Lasers and Other High Excitation Density Phenomena

An apparatus is described for studying high current density bombardment of semiconductors. It operates at voltages up to 30 kV and samples can be cooled to 28 K. The excitation density is high enough to induce lasing in many II-VI and III-V compounds at both 77 K and room temperature. The emission spectrum over a range of current densities is useful in characterizing the doping and impurities in semiconductors.

Far-field patterns of electron-beam pumped semiconductor lasers

Laser action is described for total internal reflection modes such that the far-field pattern is a circular ring surrounding the crystal in a plane perpendicular to the rectangular cavity faces. A number of recent experiments have shown that this far-field pattern can be observed in GaAs samples as well as in ZnO and CdS. Experiments are reported for single crystals at a temperature of 77°K pumped by a low-voltage electron beam using 100-ns low-duty cycle pulses. Photographs of the far-field pattern show a narrow line extending 360° around the axis of the crystal and having an angular width of 5 to 10°. Photographs of the near-field pattern indicate that the laser light is emitted in quadrants at the four corners of the rectangular cavity, combining at large distances to produce a 360° pattern. Experimental results on a number of CdS crystals of various thicknesses show that the voltage threshold for lasing (at constant current density) for the total internal reflection mode varies approximately as the 0.7 power of the crystal thickness. Losses from total internal reflection are negligible, and for CdS and ZnO platelets absorption losses are also so small that lasing can occur when the penetration depth of the electrons is only 1/40 of the total crystal thickness. Because of these low losses, lasing has been observed in ZnO and CdS at 2.5 keV and a current density of about 5 A/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> for crystal platelets approximatley 2 microns thick. Since the penetration of a 2.5 keV electron is only about 500 Å, this indicates that surface losses in CdS and ZnO with as-grown surfaces are also small. A similar thickness dependence is reported for GaAs doped with <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1.5 \times 10^{19}</tex> Zn atoms/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> , but absorption losses appear to be higher. Thus a 2-micron-thick crystal of GaAs pumped with an electron beam of the same current density as above lases with a voltage threshold of 10 keV. The threshold voltages measured for ZnO, CdS, and GaAs are considerably lower than any previously reported for electron-beam pumped semiconductor lasers.