Report on Lasers '83

The first 83 and the next 83: perspectives on neurotoxicology.

This commentary depicts the author's history, and how it became interwoven with neurotoxicology. Born in 1925, most of his life spanned a century burdened with calamitous wars as well as revolutionary developments in science. Aviation played a large role in the century's wars and in the author's outlook on the world. He moved from a literary perspective, after his war experiences, to one govern...

Helical Large-Core Fiber Lasers Final Report

Temperature Effect on THz Quantum Cascade Lasers

A simple semi-phenomenological model, which accurately predicts the dependence of thresholdcurrent for temperature of Resonant-phonon three well quantum cascade laser based on verticaltransitions is offered. We found that, the longitude optical phonon scattering of thermally excitedelectrons is the most important limiting factor for thermal performance of high frequency THz QCLs.In low frequenc...

Demographic Influences on Economic Growth, 1968-83

This paper describes an econometric investigation of the effects of population growth on the growth of output. A structural model yields an equation expressing output growth as a function of both demographic and nondemographic variables. This equation is estimated from data on 142 six-year growth periods in 85 countries at all levels of per capita output. Higher fertility is found to lower outp...

ON OPTIMAL NOZZLE SHAPES OF GAS-DYNAMIC LASERS

Pontryagin's principle is used to study the shape of the supersonic part of the nozzle of a carbon dioxide gas-dynamic laser whose gain is maximal. The exact shape is obtained for the uncoupled approximation of Anderson's bimodal model. In this case, if sharp corners are allowed, the ceiling of the supersonic part consists of a slant rectangular sheet followed by a horizontal one; otherwise...