The filtering characteristics of coated phase-shifted long-period fiber grating (LPFG) is analyzed by the coupledmode theory together with the transfer matrix method. The effects of introducing single and multiple phase shifts at various locations along a LPFG are analyzed, and the influences of the film parameters on the spectral characteristics are also studied. It is shown that the number, location and value of the phase shifts will affect the LPFG filtering characteristics. The loss peak of transmission spectrum decreases with the increase of film thickness, and the peak position shifts with the film refractive index. Compared with the non-coated phase-shifted LPFG, the coated phase-shifted LPFG not only has the similar desirable filtering characteristics, but also has a flexible adjustment ability to transmission properties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.