Narrow-Line Fiber-Coupled Modules for DPAL Pumping

Author: Tobias Koenning
Sunday, March 01, 2015
DILAS Diodenlaser GmbH

A new series of fiber coupled diode laser modules optimized for DPAL pumping is presented, featuring greater than 400W from a 600µm core fiber of 0.22NA. Addressing one of the key challenges in DPAL pumping, the modules achieve a spectral width of <<0.1 nm and wavelength tunability of +/- 0.15 nm. A limiting factor in the reduction of the spectral line width is the optical absorption induced thermal gradient inside the VHG. Simulated profiles and demonstrated techniques to minimize thermal gradients will be presented. Data is shown for potassium pumping at 766 nm, with full applicability to other wavelengths of interest.