Photonic crystal distributed feedback quantum cascade laser fabricated with holographic technique

Electrically pumped, edge-emitting, singlemode operation of a two-dimensional photonic crystal distributed feedback (PCDFB) quantum cascade laser emitting at ~7.8 mum is demonstrated. The two-beam holographic technique combined with wet-etching process is successfully used to define a square-lattice PCDFB structure on the top grating layer of the laser. This simple PC fabrication method may open e...