Fabrication and Study of Magneto Optic Waveguides using Direct Laser Writing

Photonic integrated circuits (PICs) have great potential to outperform their electronic counterparts. However, realization of these PICs requires integration of crucial optical components, such as optical isolators. Currently, isolators fabricated with inorganic crystal technology cannot be easily integrated into PICs. The objective of this summer’s research project is the fabrication and study of polymer waveguides with magneto-optic (MO) properties. This research will provide the building blocks for a compact optical isolator, which can be easily incorporated into PICs.  Our waveguides are rendered magneto-optic by introduction of magnetite nanoparticles into the waveguide’s polymer core or cladding. In the presence of an external magnetic field, these magnetite nanoparticles will produce Faraday rotation as polarized light propagates through the waveguide. Our MO waveguides will be fabricated using simple polymer deposition techniques and patterned using Direct Laser Writing (DLW), a highly reproducible and mask-less lithography method. We develop Labview software libraries for rapid prototyping of various waveguide geometries, such as linear waveguides and couplers. Fabricated waveguides are then tested in the lab to measure Faraday rotation and optical loss.  Throughout this research, key waveguide and fabrication parameters will be optimized to maximize Faraday rotation while minimizing optical loss. Preliminary data suggests that our process leads to the creation of low-loss waveguides with significant Faraday rotation.