Quantum-Cascade Vertical-Cavity Surface-Emitting Laser

This letter shows the possibility of stimulated emission in quantum cascades (QCs) embedded in a vertical cavity and proposes a first design for the QC vertical-cavity surface-emitting laser (QC VCSEL). In the proposed design, the top VCSEL mirror is a monolithic high-refractive-index contrast grating, which serves as both an optical coupler and as the region in which the vertical component of the electrical field is induced, enabling stimulating emission from the QCs. Using a three-dimensional, fully vectorial optical model combined with an electrical model and gain model, the distribution of the optical field, threshold current, emitted optical power, and wall-plug efficiency of a 9 mu m AlInAs/InGaAs/InP QC VCSEL are simulated.