Applications of Nonlinear Optical Thin Films

Abstract

AbstractMany approaches to fabrication of nonlinear optical and electro-optical thin-film materials are currently under investigation including: epitaxial inorganic films; polycrystalline inorganic materials; organic nonlinear moieties poled in polymer hosts; and poled amorphous inorganic materials. For each of these approaches there are a variety of characteristics and constraints that impact the ultimate uses. These are discussed in the context of signal processing and transmission applications such as optical interconnects and integrated optics. Almost universally, integration with the Si materials and processing that dominates current computer technology, or with the III-V materials that dominate optoelectronics technology, are major factors in the attractiveness of a technology direction. A relatively recent development is the observation of a strong nonlinearity in fused silica, χ(2) ∼ 1 pm/V, poled by modest temperature and electric-field stress. Temperature-dependent dynamic and spectroscopic measurements suggest that mobile-ion species such as Na+, as well as non-bridging oxygen bond re-orientation under a strong field, play a role in the nonlinearity.