A heterogeneous quantum cascade laser, consisting of multiple stacks of discrete wavelength quantum cascade stages, emitting in 5.9-10.9 μm, wavelength range is reported. The broadband characteristics are demonstrated with a distributed-feedback laser array, emitting at fixed frequencies at room temperature, covering an emission range of ∼760 cm-1, which is ∼59% relative to the center frequency. By appropriate choice of a strained AlInAs/GaInAs material system, quantum cascade stage design and spatial arrangement of stages, the distributed-feedback array has been engineered to exhibit a flat threshold current density across the demonstrated range.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics