Terahertz sources based on difference-frequency generation near exit facets in dual-wavelength mid-infrared quantum cascade lasers

摘要

We report novel quantum cascade laser sources based on difference-frequency generation in nonlinear sections localized near exit facets. This new approach allows for infrared-to-terahertz conversion efficiencies above 1mW/W². Experimentally, devices operating at 4THz are discussed.