SBIR Phase I: High Pulse Energy Mid-IR Vertical External Cavity Surface Emitting Lasers (VECSELs)

This Small Business Innovation Research (SBIR) Phase I project will address the need for high pulse energy laser sources operating in the mid-infrared (mid-IR) spectral region. Currently available lasers sources are limited in their capabilities. Wavelength selection and maximum output powers are limited, and efficiency, reliability and costs are also issues. High-power vertical external cavity surface emitting laser (VECSEL) development which employs multiple chip arrangements has the potential to reach wavelengths that are not easily attainable in a very compact package. In addition, the introduction of multiple gain elements inside the laser cavity provides a means for power scaling and extreme broadband mid-IR laser tuning. This also makes it possible to improve upon the conversion efficiency of other parametric oscillator laser sources. Using a high power doubly-resonant two-color T-cavity VECSEL, efficient difference frequency conversion will be achieved. High pulse energy in the mid-IR spectral region will be demonstrated through a novel design in which one of the VECSEL chips will be pulsed while operating the second color under continuous wave operation. The broader impact/commercial potential of this project is wide ranging due to the flexibility of the design. The goal of the proposed work is an innovative approach to the development of a new class of high pulse energy laser sources at wavelengths that are currently difficult to achieve. In addition to the application rich mid-IR, the laser design can easily be extended to other wavelengths in the far-IR, THz, visible, and UV portions of the spectrum. The approach can have a significant impact in various fields of science and engineering. The discoveries made within the scope of this program will have a transformative impact in mid- to far-IR lasers and benefit a number of disciplines including: laser surgery, dental surgery, dermatology, atmospheric monitoring, chemical sensing, and a broad range of defense applications including LADAR and laser range finding. In addition to the technological impact, the proposed research will cover multiple disciplines in science and engineering including high energy material properties, semiconductor physics, nonlinear optics and laser physics which will provide a unique research opportunity.