Tunable Terahertz-Frequency Lasers Based on Semiconductor Nanocrystals

ALTAIR Center proposes to develop a new class of tunable terahertz laser sources based on an active laser material fabricated from spherical semiconductor nanocrystals (quantum dots) incorporated into an optical medium transparent in terahertz-frequency range. Due to the strong Stark effect, recently discovered in semiconductor nanocrystals, the transition frequencies can be shifted by an applied low electric voltage that allows developing THz lasers tunable in a wide frequency range. In the proposed implementation, the nanocrystal composites will be incorporated into silicon waveguide structure working as an optical resonator for nanocrystal emitters. That enables on-chip integration of the THz laser sources and terahertz photonics with silicon microelectronics. All key components of the proposed device are either commercially available or routinely fabricated in many laboratories. In Phase I, we will prove feasibility of the proposed concept, evaluate optimum parameters of the required optical elements, and identify cost-effective technology for fabrication of the THz laser. In Phase II, the technology will be completely optimized and applied to fabrication of the prototype THz lasers tunable in a wide range of terahertz frequencies.