Broad area photonic crystal distributed feedback quantum cascade lasers emitting 34 W at λ ∼ 4.36 μm

We demonstrate room temperature, high power, single mode, and diffraction limited operation of a two dimensional photonic crystal distributed feedback quantum cascade laser emitting at 4.36 mu m. Total peak power up to 34 W is observed from a 3 mm long laser with 400 mu m cavity width at room temperature. Far-field profiles have M(2) figure of merit as low as 2.5. This device represents a significant step toward realization of spatially and spectrally pure broad area high power quantum cascade lasers. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3496043]