A linearly chirped in-fiber Bragg grating is reported that can compensate at 1549 nm for the dispersion [ approximately -19 ps/(nmkm)] of standard telecommunications optical fiber optimized for 1300-nm operation.
The growth rate of fiber Bragg gratings written using 193 nm light from an ArF excimer laser is linearly proportional to the laser pulse energy density for fibers with high germanium doping but proportional to the square of the pulse energy density for standard telecommunications fibers with low germanium concentration. The two-photon process in standard fibers yields refractive index increases that saturate around 10−3, an order of magnitude improvement over previous results in this type of fiber without sensitization treatment. The two types of photoinduced refractive index gratings have comparable thermal stability and preserve about 50% of their initial magnitude after 30 min at 600 °C.
rate = 50pulsek) until the maximum reflectivity reached 10% (-IOdB), typically requiring a few tens of seconds. The photoimprinted Bragg grating resonates at a centre wavelength of 1557.5nm with a 3dB bandwidth of 1.5nm (see Fig. 2). The sidelobes are ill defined and more than 26dB below the reflection peak. For comparison (also in Fig. 2), a Bragg grating with a sim-Conclusion: We have achieved the effective apodisation of the reflectivity of photoimprinted Bragg gratings by tailoring the diffraction efficiency of the phase mask. A suitable chosen Gaussian profile of diffraction efficiency has reduced sidelobe levels by more than 14 dB.
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.