Low-threshold, high-power zero-order lateral-mode DQW-SCH metal-clad ridge waveguide (AlGa)As/GaAs lasers

Metal-clad ridge waveguide (MCRW), double quantum well, separately confined heterostrucuture (DQW-SCH) lasers have been fabricated having continuous-wave (CW) threshold currents of 10?12 mA and external differential quantum efficiencies of 41?46% per uncoated facet. Light/current characteristics are linear to >70 mW, and zero-order lateral mode operation was measured at 56 mW. The CW burn-off power density is nearly double the best previously reported value.     

The static and dynamic characteristics of single and multiplephase-shifted DFB laser structures

The influence of longitudinal mode spatial hole burning (LMSHB) on the performance of distributed feedback (DFB) laser structures is examined in detail. A comprehensive model has been used to interpret the experimental results and to construct a theoretical framework that was utilized to develop more advanced device designs. An increasing side mode intensity with output power, movement of the lasing mode relative to the stopband, and curvature of the light-current characteristic at low power can all be manifestations of the influence of LMSHB on the static device performance. The dynamic behavior can also be affected, with extended wavelength chirp and amplitude patterning effects on the timescale of the effective carrier recombination time being particularly important     

Future technology challenges in distributed interactive simulation

The paper examines the changes in computer and communications capabilities over the next 10-15 years which are most likely to affect the central components of distributed interactive simulation (DIS): manned simulators, synthetic environments, and semi-automated forces (SAF). Because these components of DIS are currently very resource intensive, improvements in computer and communications capabilities translate into direct and immediate improvements in DIS capabilities. These improved capabilities in turn allow DIS to contribute in much broader arenas, enhancing troop readiness and reducing system acquisition costs. These improvements will not all come automatically, however. Substantial planning is required to ensure that DIS can take advantage of the coming changes, rather than being overcome by them