Integrated photonic devices play an important role in optical sensors and optical communication networks. Many different waveguide materials can be used for integrated guided wave devices.
Most bulky optical components are made from materials from the III-V group such as gallium arsenide, indium phosphide, or the electro-optic crystals such as lithium niobate. In addition, silicon and polymer materials have been successfully used in photonics integration. In fact, for the being time, silicon has been accepted as a key material in photonic industry and silicon-photonics has become an important part of photonics research. However, silicon suffers from some obstacles especially regarding the optical nonlinearity that has a key role in indirect optical modulators. For instance, the bulk silicon has very small (theoretically nothing) second-order nonlinearity owing to inversion symmetry of the crystal lattice. Thus, one needs to think about other materials for use in hybrid or standalone structures. In addition, there are applications for which inorganic compounds are not perfectly appropriate; those ones requiring, for example, optical nonlinearity, wavelength tunability, large areas, mechanical flexibility and low-cost fabrication processes. Organic polymers are promising materials for such photonic applications as they merge the material properties of plastics with high optical cross-sections, large and ultrafast nonlinear responses, and broad spectral tunability. In the field of optical communications, inorganic materials and their related technologies will not be probably suppressed by organic materials in many devices such as inorganic semiconductor lasers and detectors. So the concept of silicon-organic hybrid photonic integration can use both the benefits of useful optical properties of organic materials and the silicon technology.
It is worth noting that several active and passive polymer integrated optical devices have been fabricated, and a variety of functions and devices, such as optical waveguides, variable optical attenuators, electro-optic modulators, 3D holography, filtering, coupling, routing, and switching have been demonstrated in the literature.
To find out more about the applications of organic and polymer compounds in photodetctors, light emitting diodes and photovoltaics, you are encouraged to see our research directions regarding organic electronics in the research page.