This paper is a review of semiconductor laser work. The principles of operation are discussed. The stress is on work since early 1964. The present state-of-the-art in GaAs junction lasers is described.

http://ieeexplore.ieee.org/iel5/5/31089/01447045.pdf

Semiconductor lasers

The paper is a survey of experimental and theoretical results on exciton states in crystals of xenon, krypton, argon and neon. The absorption and luminescence spectra of the crystals and the band structure of electron and exciton states are analysed. Some features of the exciton-phonon interaction in pure and doped crystals are discussed. In contrast with other types of molecular crystal, those of rare gases can simultaneously support free and localized excitons. All features of the exciton spectra, in particular the hydrogen-like series of light absorption, the rich pattern of luminescence and the absorption and emission bands due to impurity centres, have been given a natural explanation in terms of the intermediate-radius exciton strongly bonded to the crystal lattice. These investigations of excitons in atomic cryocrystals have revealed a number of new effects and extended our knowledge of the cooperative excitation states of dielectrics.

Excitons in rare-gas crystals

An 800 l liquid xenon scintillation γ -ray detector is being developed for the MEG experiment which will search for μ + → e + γ  decay at the Paul Scherrer Institut Absorption of scintillation light of xenon by impurities might possibly limit the performance of such a detector We used a 100 l prototype with an active volume of 372 × 372 × 496 mm 3 to study the scintillation light absorption We have developed a method to evaluate the light absorption, separately from elastic scattering of light, by measuring cosmic rays and α sources By using a suitable purification technique, an absorption length longer than 100 cm has been achieved The effects of the light absorption on the energy resolution are estimated by Monte Carlo simulation

Absorption of scintillation light in a 100 l liquid xenon γ-ray detector and expected detector performance

A review of recent developments in high-pressure pulsed molecular lasers is presented. Included are some experimental results on TEA lasers, E-beam lasers, and lasers using Blumlein excitation. Discussions of the kinetic modeling, the parametric behavior, and the characteristics of uniform discharges in the high-pressure pulsed CO 2 laser are given. Recent results on pulse-initiated chemical lasers, extremely high-pressure lasers, and high-repetition-rate TEA lasers are also discussed. Efforts to control and use the output from these devices are described, and an extensive list of references is given.

High-pressure pulsed molecular lasers

A review of the status of research towards achieving lasing action in the vacuum ultraviolet and soft X-ray spectral regions is presented. An analysis of the general problems likely to be encountered is accompanied by numerical results for those approaches currently considered promising. Progress on each approach is detailed and various possible methods of verifying the presence of gain with their relative merits are discussed. Research areas requiring Application of short-wavelength lasers also are given.

N. G. Basov

Papers

Luminescence of condensed Xe, Kr, Ar and their mixtures in vacuum region of spectrum under excitation by fast electrons

Cathodoluminescence of Solid Xenon in the Ultraviolet Region of the Spectrum

Exciting a Semiconductor Quantum Generator (Laser) with a Fast Electron Beam

CERTAIN CHARACTERISTICS OF THE GENERATION OF OPTICAL RADIATION IN CdS AS A RESULT OF ELECTRON EXCITATION.