Abstract

Since the introduction of the Vertical-External-Cavity Surface-Emitting-Laser (VECSEL) [1] in 1997, multi-Watt output, M² ~ 1.0 – 1.3, have been demonstrated in CW and pulsed operation in UV to mid IR spectral range, on the fundamental wavelength or in combination with intracavity frequency mixing. However, in the red wavelength range, with AlGaInP material system, power scaling is ultimately limited by low optical efficiency of 19 % or lower. High power operations in this material system [2–3] were demonstrated at fairly low operating temperature despite the effective cooling scheme. Since low operating temperature is advantageous to the AlGaInP VECSELs, one solution to improve the output and the efficiency is reducing the generation of heat within the active layer due to the energy difference of pump and laser photon ("quantum defect"). This can be done by means of quantum-well (QW) pumping instead of the typical barrier pumping [1, 4] scheme.

© 2015 IEEE