Northrop Grumman Cutting Edge Optronics has developed a laser diode array package with minimal bar-to-bar spacing. These High Density Stack (HDS) packages allow for a power density increase on the order of ~ 2.5x when compared to industry-standard arrays.
This work contains an overview of the manufacturing process, as well as representative data for 5-, 10-, and 20-bar arrays. Near-field and power vs. current data is presented in each case. Power densities approaching 15 kW/cm² are presented. In addition, power and wavelength are presented as a function of pulse width in order to determine the acceptable operational parameters for this type of array. In the low repetition rate Nd:YAG pumping regime, all devices are shown to operate with relatively low junction temperatures.
A discussion of future work is also presented, with a focus on extending the HDS architecture to reliable operation at 300W per bar. This will enable power densities of approximately 25 kW/cm².