Mid-Infrared Electroluminescence in Quantum Cascade Structures with InP/InGaAs Active Regions

We report on the mid-infrared emission from electroluminescent devices with quantum cascade active regions based on InGaAs/InP heterostructures. We observe emission at lambda~12 mum from two different structures and compare their emission characteristics based on the different band structure designs. Their relevance in view of the realization of new InP-based quantum cascade lasers with Aluminum-free waveguides is discussed.