This Small Business Innovation Research Phase I project has the primary objective of developing nonlinear optical (NLO) thin films on GaAs substrates. NLO films on GaAs offer a number of potential applications in integrated optics. With the thin film approach it is possible to develop an integrated optics technology in which light sources, nonlinear optical components and detectors may be developed on the same substrate. At present, the growth of device quality films on GaAs remains a major technological challenge. Until now, the performance of the NLO films on GaAs has not exceeded or equaled the performance of the bulk counterparts. Therefore an immediate need exists for an improved growth process for promoting superior quality films compared to those presently available. Also, for integration with GaAs, lower growth temperatures are required. The primary objective of the proposed Phase I effort is to explore the potential of ion beam assisted pulsed laser deposition (IBPLD) as a new low temperature technique for the growth of high quality nonlinear optical films on GaAs substrates. The approach will require synthesis of NLO films by IBPLD technique and identification of critical process parameters that are compatible with GaAs processing leading to optimum nonlinear optical properties. As a prototype, KTa 0.52 Nb0.48 O3 films with a Tc of 88 C will be epitaxially deposited on GaAs substrates with MgO buffer layers and their nonlinear optical performance will be evaluated. The nonlinear optical films on GaAs offer unique device possibilities in optical signal processing, optical computing and beam steering. The film process technology is generic and could lead to a new generation of integrated optical devices. For Neocera, the nonlinear optical thin film technologies and commercial IBPLD systems, as commodity products, could further expand the existing market base.
