This research focuses on the crystal growth and study of a wide range of promising undoped and doped nonlinear optical and laser gain materials. Such materials including binary semiconductors such as GaP, GaAs, ZnSe, ZnTe, etc. grown on orientation-patterned templates (OP) take advantage of quasi-phase matching (QPM) frequency conversion to generate output in the mid- and longwave infrared. The frequency range of such sources could be extended to the UV and the THz region by involving wide band semiconductor materials such III-Nitrides. The typical growth method is hydride vapor phase epitaxy, including the heteroepitaxial growth of related ternaries with the aim of combining the best nonlinear optical properties in one material structure. Since many of the explored to date materials have achieved fundamental or technological limits heteroepitaxy will be the leading approach in the vapor phase growth, especially in the cases when large area native substrates are unavailable (ZnSe, ZnTe, GaSe) or their quality is unacceptably low (GaP). Heteroepitaxy will be also used for the growth of low-dimensional materials such as GaSe, as well for thick growth of some optical materials on traditional semiconductor substrates such as Si or Ge for potential electronic and optoelectronic applications.
We are also interested in birefringently phase-matched nonlinear crystals grown via Bridgman, Czochralski, or similar techniques, to improve upon existing crystals like ZGP and CSP. This involves exploratory growth of promising novel crystals for characterization and further development, many of which receive only cursory treatment in the literature based on power samples. Growth and study of some temperature resistive organics with high nonlinearity for the purpose of growth or fabrication of novel hybrid organic/inorganic QPM structures will be also a part of this research. Laser gain materials include host crystals such as fluorides, tantalates, or oxides doped with rare earth or other active ions for lasing in the mid- or longwave IR. Research will expand the repertoire of gain media available for laser source development, building in part upon results obtained with thin film samples. Together, the nonlinear and laser crystals studied will provide a foundation for development of high power/energy, widely tunable coherent sources operating in the mid and longwave infrared. There has been sustained interest in such sources for a variety of applications in areas such as defense, security, industry, medicine and science.
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Crystal growth; hydride vapor phase epitaxy; heteroepitaxy; nonlinear optical materials; electronic materials; III-V and II-VI semiconductor materials; low-dimensional materials; inorganic and organic materials; common substrates; oriented-patterned templates; frequency conversion devices; quasi-phase matching