SBIR-STTR Award

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

ALTAIR Center in cooperation with the NanoTech Institute at the University of Texas at Dallas proposes to develop a new class of terahertz (THz) lasers generating about 1 mW in the frequency range 0.3-10 THz at room temperature. The proposed concept is based on employing the semiconductor nanocrystals (quantum dots). The nanocrystal emitters are optically pumped by commercially available powerful and cost-efficient laser diodes operating in the near-infrared region of spectrum. The proposed concept allows complete preventing the nonradiative Auger processes that are a major obstacle for lasing on nanocrystals. Because transition frequencies in the nanocrystals are easily controlled by appropriate choice of nanocrystal radius and semiconductor material, the proposed laser sources can cover the entire THz-frequency range. In the course of Phase I project, we already proved feasibility of the proposed concept of THz lasing on semiconductor nanocrystals by analytical studies and numerical modeling. In Phase II the prototype THz laser will be fabricated, optimized tested and delivered to DoD for immediate implementation.

Keywords:
Terahertz Lasers, Semiconductor Nanocrystals, Quantum Dots, Microchip Lasers, Laser Diodes, Auger R