Room Temperature Terahertz Quantum Cascade Laser Source Based On Intracavity Difference-Frequency Generation

We report on our progress in the development of a terahertz quantum cascade laser source based on intracavity terahertz difference-frequency mixing in a dual-wavelength mid-infrared quantum cascade laser with the active region engineered to possess giant second-order nonlinear susceptibility. In this letter, we demonstrate devices that operate in mid-infrared at lambda(1)=8.9 mu m and lambda(2)=10.5 mu m and produce terahertz output at lambda approximate to 60 mu m via difference-frequency generation with 7 mu W output power at 80 K, 1 mu W output at 250 K, and still approximately 300 nW output at 300 K. (c) 2008 American Institute of Physics.