Line-Narrowed Diode Pump Sources for DPAL Systems

Laser diode arrays are a major component cost for advanced high-power laser systems such as the Diode-Pumped Alkali Laser, and numerous other military and industrial laser systems. The most critical design feature of diode pump arrays for Diode-Pumped Alkali Lasers is the wavelength match of the absorption line and the linewidth of the pump. The linewidth required for efficient pumping of alkali lasers is very stringent and affects the system efficiency. The efficiency of the system drops dramatically as the linewidth of the pump array broadens to several hundred gigahertz. Linewidth narrowing methods involving external-cavity gratings have difficulty achieving this wavelength tolerance for laser diode arrays because of the"smile"in the laser bar. Other techniques are also impractical to manufacture, and integrated gratings suffer from low yield and high cost. A new technique is needed to meet the pump requirements of Diode-Pumped Alkali Lasers. Vega Wave Systems, Inc. proposes to use a recently developed technology for laser diodes that promises to achieve the necessary wavelength stabilization with narrow linewidth at a greatly reduced manufacturing cost.