The RLE Millimeter-wave and Terahertz Devices Group develops novel devices operating from millimeter-wave to THz frequencies, and explores system-level applications enabled by those devices. Specifically, the group is working on high-performance THz quantum cascade lasers based on intersubband transitions in quantum wells; ultrafast time- and phase-resolved study of dynamics in quantum structures; sensing and real-time imaging THz systems for a variety of applications including remote sensing, biomedical imaging, and security.