Future prospects

smaller than the brightness values that were achieved for the RWG lasers. Bright-nesses as high as 800 MW sr⁻¹cm⁻², emitting at a wavelength of 1060 nm have been reported in the literature [37], which implies that the design of the tapered DBR lasers measured here is not optimal. The low brightness can mainly be attributed to the too wide opening angle of the tapered section, which allows the propagation of higher order modes.

6.2 Future prospects

The RWG lasers with an asymmetric structure showed superior behavior in terms of stability, beam quality and brightness, compared to the symmetric structure RWG lasers. However, the amount of asymmetric RWG lasers components that were ana-lyzed was very small. In order to nd the most optimum design parameters, a much wider variety of dierent RWG width and etch depth combinations need to be ana-lyzed. The lifetime of the RWG lasers could also be measured to see how the sym-metric and asymsym-metric structure compare in terms of reliability.

The tapered DBR lasers displayed poor brightness due to poor beam quality. The poor beam quality in the SA direction is likely due to unoptimized design para-meters, such as the opening angle of the tapered section, which may be too large.

An extensive analysis of tapered laser components with dierent design parameters should be performed in order to nd the most optimal parameters that lead to the highest brightness. In order to further improve the beam quality, an asymmetric epi-taxial structure similar to the one used in this thesis could be used, as it was found to lead to improved beam quality in both the SA and FA directions. This would also make it easier to collimate the beam in the FA direction, since the divergence angle would be narrower.

66

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