Development of quantum cascade lasers for high peak output power and low threshold current density

In order to model various structures, we developed band structure and waveguide simulation tools to help tailor the initial design to demonstrate lower threshold current density and higher device efficiency. The quantum cascade laser emitting layers consist of a series of stacked emitters, or active regions, which are capable of demonstrating multiple photon emission per input electron above threshold. Shown is a typical waveguide schematic and band structure for a QCL based on interminiband transitions.