Research is being pursued on enabling technologies for high power solid-state lasers to meet the needs of the Army and the other armed services. These lasers are more rugged and compact than gas lasers, but have not been scaled to sufficiently high powers while maintaining good beam quality. We are investigating technologies for scalable gain media, thermal management, and beam quality improvement. These include ceramic gain media, which are as good as single crystals in most regards, are mechanically stronger, and can be scaled to larger sizes. We are pursuing the use of these materials and others at cryogenic temperatures, where key thermal and optical properties are much improved over room temperature. We are particularly interested in laser operation at wavelengths near 1.6 microns in Er-doped solids, since this wavelength range offers much improved eye safety, and where ongoing advances in diodes lasers offer the potential for greatly improved efficiency and reduced thermal distortion. Other gain media of interest are fibers, which offer considerable beam quality and efficiency advantages but require innovative designs to enable sufficient power scaling. We are also investigating special materials and geometries to promote heat removal from laser gain media and to further improve beam quality, beam correction techniques based on stimulated light scattering (Brillouin and Raman).
Our laboratories have a range of laser and spectroscopic tools for these studies. These include several types of diode lasers and arrays for efficient pumping of laser materials and a range of homemade laser cavities to test materials and thermal management approaches. We also have up-to-date spectrometers for absorption and emission spectroscopy, and cryostats for both laser and spectroscopic studies as a function of temperature.
Newburgh GA, Dubinskiy M, Merkle LD: Electronics Letters 43: 286, 2007
Dubinskiy M, Zhang J, Kudryashov I: Applied Physics Letters 93: 031111, 2008
Laser material; Solid-state laser; High power laser; Ceramics; Phase conjugation; Heat spreader; Eye safe; Fiber laser;