A method has been developed to embed a variety of different types of nanoparticles into
microstructured polymer optical fibers (mPOFs). This figure shows a mPOF with cobalt
nanoparticles embedded within the core of the fiber to produce a magneto-optical effect. In this
paper, rotation of the plane of polarization in relation to the dopant concentration and magnetic
field strength is demonstrated. The magneto-optical effect coupled with careful tailoring of the
microstucture allows for a number of potential applications, including magnetic field sensors,
current sensors, and in-fiber optical isolators.