Photonic crystal fibers (PCF) are attractive for chemical, biomedical, and environmental sensing applications. The freedom in designing the microstructure geometry provides a unique platform for realizing the desired modal dispersion, birefringence, confinement and multiplicity characteristics. Of significant importance to these features, chemical, biological and inorganic materials can be introduced to the PCF by selective hole infiltration or deposition techniques. Novel PCF sensor designs often encompass structural and electromagnetic field features spanning multiple orders of magnitude in variation, e.g. sub-wavelength metal films and tightly confined surface plasmonic modes in a PCF with wavelength-scale mode and air-hole radii having cladding dimensions of 100 times of the wavelength. These properties require a mode solver that can both efficiently and accurately approximate the geometry and the electromagnetic fields over the entire simulation domain.
Full Application Note