Long-wavelength diode lasers, emitting at 1.5x μm, have been optimized for maximum continuous-wave (CW) electroto- optical power conversion efficiency (PCE) and output power. A maximum CW PCE value of 50% is achieved at room-temperature from a 0.10 x 1.5 mm<sup>2</sup> diode laser with a CW output power of 2.5 W from a laser structure with a single-quantum-well (SQW) active region. Reliability tests show no degradation when run at 5A, 40°C for < 4000 hours of operation.
Incorporating monolithic distributed feedback (DFB) gratings into broad-area (BA) diode lasers results in ten times narrower spectral width and four-to-five times lower thermal shift in emission wavelength. We report on our progress to obtaining a high-power, high-efficiency DFB diode pump in the 1.4-1.6 μm wavelength range for use in industrial and military, eye-safe applications. Results for Fabry-Perot diode lasers emitting at 1530 nm are also discussed. We report on an index-guided, single-emitter design (0.15 x 0.01 cm<sup>2</sup>) capable of producing 2.5 W of continuous-wave output power at room-temperature with a peak power conversion efficiency of 50%.
Laser initiation of explosive material requires consistent achievement of specific optical power densities and extremely
high reliability under a wide variety of harsh environmental conditions. Ensuring successful and timely detonation
drives laser diode-based systems towards testing algorithms that far exceed the standard Telcordia GR-468
qualifications. As diode technology advances, options for increased power density and alternate system configurations
expand. An understanding of the basis of diode laser reliability in this application will be provided, along with key
optical system metrics for a variety of current and future LIO systems.
We present a model for 455-nm thulium-doped fluorozirconate fiber lasers co-pumped at 645 nm and 1064 nm. Twelve radiative transitions are accounted for in our model, along with cross- relaxation and cooperative upconversion processes. Blue laser output power is computed using a rate equation analysis. Relevant spectroscopic data used in our model are given, including cross-section measurements that we have performed. The results of our simulation show a good agreement with previously published experimental data. The importance of cross-relaxation processes is discussed. The dependence of output laser power on fiber length, output mirror reflectivity, and pump powers is also addressed.