Numerical simulation supports the previous application of the classical approximation for equal zones in a cylindrical Fresnel fiber. We show that simple defects can be introduced in solid core Fresnel fibers to allow two modes to be generated. Such fibers permit grating writing to be combined with diffractive waveguides where the mode peak intensity resides in an air hole. This is extremely attractive for sensing applications.
© 2006 Institute of Electronics, Information and Communication EngineersPDF Article