Strong Bragg gratings in phosphate glass single mode fiber

摘要

Bragg gratings with reflectivities greater than 99% have been fabricated in phosphate glass single mode fibers by irradiating the fibers with 193 nm wavelength, high intensity pulses from an ArF excimer laser through a phase mask. Thermal treatment for 1000 h at temperatures up to 170℃ did not degrade the gratings and resulted in an increase in grating strength. The refractive index modulation amplitudes obtained exceed 10~(-4).