In this paper, we will show reliable lasing performance of distributed Bragg reflector tapered diode lasers (DBR-TPLs) emitting at 1180 nm more than 7 W in continuous wave operation for 3,000 h without failure. The devices feature an epitaxial layer structure with an optimized strained double quantum well in a newly developed asymmetric large optical cavity resulting in a small vertical far field emission of 16° (FWHM). The DBR-TPLs consist of a 4 mm long tapered gain-guided section and a 2 mm long ridge waveguide section containing a 1 mm long DBR-grating. Owing to the integrated DBR-grating the investigated devices show predominantly longitudinal single mode emission between mode hops and an excellent beam quality with a power content of more than 75% in the central lobe at 8 W. Therefore, DBR-TPLs emitting at 1180 nm have become a highly efficient and narrowband light source, which can be used for efficient frequency doubling and enable various applications. In this paper epitaxial, device and emission characteristics will be discussed in detail.
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