Abstract: The present invention is directed to the development of compact, coherent sources emitting in the terahertz frequency region using interface phonons. In accordance with a preferred embodiment, a semiconductor heterostructure light emitting device includes a quantum cascade structure having at least an upper lasing level and a lower lasing level. The system uses heterostructure interface phonon bands to depopulate the lower lasing level of at least a three level semiconductor device. The device includes multiple coupled quantum well modules. In alternate preferred embodiments, the device includes quantum dot layers and/or, quantum wire structures, and/or mini-bands in a superlattice, for example, GaAs/AlGaAs superlattice. The phonons in the device improve efficiency, decrease the threshold current and result in system temperatures that are as high as room temperature. The semiconductor device provides emission of terahertz radiation.

Abstract: The present invention is directed to the development of compact, coherent sources emitting in the terahertz frequency region using interface phonons. In accordance with a preferred embodiment, a semiconductor heterostructure light emitting device includes a quantum cascade structure having at least an upper lasing level and a lower lasing level. The system uses heterostructure interface phonon bands to depopulate the lower lasing level of at least a three level semiconductor device. The device includes multiple coupled quantum well modules. In alternate preferred embodiments, the device includes quantum dot layers and/or, quantum wire structures, and/or mini-bands in a superlattice, for example, GaAs/AlGaAs superlattice. The phonons in the device improve efficiency, decrease the threshold current and result in system temperatures that are as high as room temperature. The semiconductor device provides emission of terahertz radiation.