Tailoring the wavelength of semiconductor disk lasers

Abstract

Optically-pumped semiconductor disk lasers (SDLs) represent a proven approach for generation of multi-watt output powers with excellent beam quality [1-6]. They combine many advantages of solid-state lasers with the added benefit of wavelength tailoring provided by the semiconductor gain material. During the past few years a wafer fusion technique has been used extensively in the producing of vertical-cavity surface-emitting lasers operating at the telecom wavelengths of 1.3 - 1.55 μm. This technique allows the integration of non-lattice-matched semiconductor materials, e.g. GaAs and InP, which cannot be grown monolithically. Here we describe the first wafer fused SDLs operating at the wavelength of 1.3 and 1.57 μm in both continuous-wave and mode-locked regimes. The quantum dot semiconductors provide an interesting alternative to quantum-well (QW) structures since these materials alleviate the requirement for lattice matching. Recently, we have demonstrated first quantum dot based gain medium in SDL architecture. Since then, different wavelengths have been demonstrated both in continuous-wave and mode-locked regimes with a performance comparable to quantum-well-based lasers. The (AlGaIn)(AsSb) material system establishes a steady platform for optoelectronic devices operating in the mid-infrared spectral range. Latticematched or strain-compensated structures employing InGaAsSb as an active material and AlGaAsSb for barrier and cladding layers grown on GaSb substrates are demonstrated to be compounds of choice for long-wavelength lasers and photodetectors. In this study we report an optically-pumped semiconductor disk laser emitting radiation around 2.5 μm tunable over 130 nm. To our knowledge, this is the widest spectral range reported to date at this wavelength.