This investigation demonstrates leakage coupling between fundamental-mode and high-order mode resonance based on a periodical silica thin-film long-period grating (TFLPG) that was coated on a tapered fiber when wavelengths longer than the fundamental-mode cutoff were propagated. For the leaky guiding situation, these leakage modes still may exhibit strong mode coupling in the taper with the assistance of the TFLPG when the phase-matched condition is satisfied. An extremely high tuning efficiency of 62.9 nm/°C, which is equivalent to a measurement of sensitivity of approximately 168, 182 nm per refractive index unit, is achieved. To the best of our knowledge, this sensitivity is the highest achieved for a fiber sensor to date.
Tm3+ and Dy3+ co-doped zinc-aluminum phosphate glasses were prepared in this study. Judd-Ofelt theory has been used to evaluate the three intensity parameters Ω2, Ω4 and Ω6 form the experimental oscillator strengths. The luminescence properties were investigated by excitation and emission spectra. White light emission could be induced by combined blue and yellow bands under UV excitation, and the variety of excitation wavelength could change the luminescence color.
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.