The wide range of applications in biophotonics, television or projectors, spectroscopy and lithography made the vertical external cavity surface-emitting lasers an important category of power scalable lasers. The possibility of bandgap engineering, inserting frequency selective and converting elements into the external laser cavity and laser emission in the fundamental Gaussian mode leads to ongoing growth of the area of applications for tunable laser sources. We present an intra cavity frequency-doubled VECSEL with emission wavelength around 330 nm and a maximum tuning range of more than 7nm with output powers exeeding 100mW. Frequency doubling is realized with an anti-reflection coated beta barium borate crystal, while a birefringent filter, placed inside the laser cavity under Brewster's angle, is used for frequency tuning. The fundamental laser, pumped by a 532nm Nd:YAG laser under an angle of 50° normal to the surface, is realized by a multi quantum well structure consisting of 20 compressively strained GaInP quantum wells in an AlxGa_1-xInP separate confinement heterostructure and it emits around 660 nm. The VECSEL-chip with its n-λ cavity is completed by a 55 λ/4 pairs Al_0.50Ga_0.50As/AlAs distributed Bragg reflector. Next to the optical properties of the device, we show results of different arrangements of the quantum wells, namely five times four and ten times two packages.

Date Published: 14 February 2012
PDF: 7 pages
Proc. SPIE 8242, Vertical External Cavity Surface Emitting Lasers (VECSELs) II, 82420M (14 February 2012); doi: 10.1117/12.907902

Published in SPIE Proceedings Vol. 8242:
Vertical External Cavity Surface Emitting Lasers (VECSELs) II
Anne C. Tropper, Editor(s)