We demonstrate surface emitting distributed feedback quantum cascade lasers emitting at wavelengths from 8.1 μm at 90K to 8.4 μm at 210 K. The second-order metalized grating is carefully designed using a modified coupled-mode theory and fabricated by contact lithography. The devices show single mode behavior with a side mode suppression ratio above 18 dB at all working temperatures. At 90 K, the device emits an optical power of 101mW from the surface and 199mW from the edge. In addition, a double-lobe far-field pattern with a separationof 2.2̊ is obtained in the direction along the waveguide.
ASJC Scopus subject areas
- Physics and Astronomy(all)