GOALI: High-Power Optical Materials for Micro- and Nanofabrication

Oregon State University, Corvallis OR

Investigators

Abstract

The purpose of this project is to advance our understanding of the properties that limit both high-power and short-wavelength operation of laser and nonlinear optical (NLO) crystals. In addition, new and improved materials will be developed. At present, lack of a suitable combination of high birefringence and high transparency in NLO materials is limiting direct second-harmonic conversion to deep UV and VUV wavelengths. In the future, nonlinear absorption and thermal properties are likely to become limiting factors for performance at very high-power levels. To study and address these materials issues, the optical and thermal properties of several wide bandgap oxides will be examined. Linear optical properties, thermal conductivity, and thermo-optic coefficients will be studied for high-transparency nonlinear optical crystals that will allow either direct second-harmonic conversion to wavelengths shorter than 200 nm or frequency mixing for generation of tunable VUV light. The production of high powers in solid-state lasers is largely a thermal-management issue. Substantial improvements in solid-state laser output powers and efficiencies are certainly attainable by incorporating the small energy-defect emission of Yb3+ in a very high thermal-conductivity host. To achieve this combination of properties, several new materials that are rich in Y203 and BeO will be studied and developed. Detailed spectroscopic examinations will be made on the emitting Yb3+ ion; large single crystals will be grown; thermal conductivities will be assessed; and laser properties will be established. The effects of the proposed program extend well beyond optical science and engineering, as the work has direct relevance to manufacturing and micromachining of most of the high-technology devices that are currently being produced in the electronics and telecommunications industries. Moreover, in the future, such laser systems will play important roles in connecting pico-, nano-, meso-, and microscale functions to our everyday world through the fabrication of microelectromechanical devices (MEMs,) microelectrochemical systems (MECs,) and other small photonic and biodevices. The proposed project is also important for the development of human resources in science and engineering; the area is growing rapidly and experienced scientists and engineers are needed. The program involves an international collection of researchers from a variety of disciplines in both academia and industry. Graduate and undergraduate students will be exposed to many different areas of the materials and laser sciences, providing unique research and education opportunities.