High-Power Surface-Emitting Surface-Plasmon-Enhanced Distributed Feedback Quantum Cascade Lasers

Room temperature operation of surface-emitting single-mode distributed feedback quantum cascade lasers (QCLs) operating at a wavelength around 8.5 μm is presented. The record output peak powers of 3.85 W at 160 K and 1.06 W at 300 K were obtained by an optimum grating design. A two-lobed far-field pattern with a separation of 0.35
^°
along the waveguide was observed. It is an important step to realize the practical application of surface-emitting QCLs in mid-infrared spectral range for high power in optical circuit integration.