SBIR Phase I: Broadly Tunable Room-Temperature Terahertz Quantum Cascade Laser Sources And Systems

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase I project will address the growing demand for compact broadly-tunable terahertz (THz) sources used by pharmaceutics for tablet inspection, the manufacturing sector for quality control, the medical community for diagnostic imaging, security agencies for contraband drug and explosives detection, firms developing high sensitivity chemical/biological sensors, and the scientific community active in THz research. Currently a void exists for compact and affordable source systems, particularly in the 3 - 6 THz range. We will be the first company to offer room-temperature THz systems based on semiconductor laser technology that provides narrow-band continuous wave (CW) or quasi-CW output tunable in nearly the entire 1 - 6 THz range. Our system will provide the largest spectral coverage and tuning bandwidth amongst competing commercial THz sources of similar size and operation. Our key value proposition is providing THz developers with a compact room-temperature maintenance-free turn-key THz system with unprecedented spectral coverage that is similar in size, operation simplicity, and manufacturing cost as commercially successful broadly-tunable external-cavity diode and quantum cacscade lasers. This Small Business Innovation Research (SBIR) Phase I project will demonstrate widely tunable room-temperature terahertz (THz) semiconductor laser sources and systems. Our technology platform is based on room-temperature THz difference-frequency generation (DFG) in dual-wavelength mid-infrared quantum cascade lasers (QCL). The DFG-QCL source active region is designed to support lasing at two mid-infrared frequencies. Emission at an intermediate THz frequency is made possible by quantum-engineering the active region to possess broadly distributed second-order optical nonlinearity for efficient generation from 1 - 6 THz. The laser chips will be integrated in an external-cavity (EC) system and a computer-controlled diffraction grating is rotated to select the THz emission line. The tuning range of the system will be significantly larger compared any other compact THz sources on the market, which is very important for sensing and spectroscopic applications. Room-temperature operation will enable a compact system footprint and robust housing suitable for portable operation.