Power Enhancement of a Rubidium Vapor Laser with a Master Oscillator Power Amplifier

The concept of alkali lasers was first suggested by Schalow and Townes in the late 1950s. In the 1970s, photo-dissociation of several of the alkali salts produced lasers with wavelengths ranging from the visible to the far infrared. Thirty years later, diode-pumped alkali lasers (DPAL) started rapidly gaining attention as highly efficient lasers as well as brightness converters. These systems partly owe their high efficiencies to the very small energy differences between the pump and lasing levels. Due to recent technological advances in the field of solid-state lasers, direct-diode pumping has provided the efficient, yet compact method for excitation.To date, to increase the power of alkali laser systems, higher intensity pumping of the gain medium has been used. However, there is a critical limit that can be achieved on these smaller scale systems due to decomposition of the gain medium due to excess thermal loading. One way to mitigate this problem is to use an amplifier or an amplifier chain. As demonstrated with solid-state lasers, this is a possible way to increase system power loading while alleviating the thermal management issues of the laser by spreading the heat out over several pieces of gain medium.