Array-Format Microchip Semiconductor Disk Lasers

We report a detailed study of an array-format 1.055- mum microchip semiconductor disk laser which uses a microlens-patterned diamond both as an array of stabilizing output coupling mirrors and a heatspreader. A thermal study of the devices, using a finite element analysis, is carried out and confirms the thermal management capabilities and power scalability of this microlensed diamond configuration. This design is then exploited to perform a systematic study on a set of microchip lasers having the same semiconductor structure but microlenses with differing characteristics. The transverse mode characteristics of individual semiconductor disk lasers are found to depend on the mode-matching condition and on the microlens aperture size. Mode-matched single-device emission in the fundamental mode (M² ~ 1.1) with a pump-limited output power of 70 mW is demonstrated. The experimental measurement of the thermal resistance of the device is also shown to agree with the finite element analysis. Finally, array operation, while pumping with a single beam, is reported.