GaSb-based tapered diode lasers at 1.93 µm with 1.5-W nearly diffraction-limited power

High-power high-brightness 1.93-µm wavelength (AlGaIn)(AsSb) tapered diode lasers with a narrow vertical waveguide design are reported for the first time. A nearly diffraction-limited continuous-wave output power of 1.5 W together with a remarkable low fast axis divergence of 43° full-width at half-maximum have been demonstrated. The maximum brightness amounts to 32 MW/cm2 sr.