Author:
Hewlett S. J.,Love J. D.,Meltz G.,Bailey T. J.,Morey W. W.
Abstract
A series of blazed, or tilted gratings were fabricated in both depressed-cladding (AT&T Accutether) and matched-cladding (Corning SMF-28) single-mode fibre. In each case, a phase mask was orientated to set the nominal blaze angle (i.e., the complement of the angle between the fibre axis and the etched lines in the mask) from 0° to 3°. The fibres were soaked in hydrogen at 2120 psi and 97.6°C for 15 hours to enhance their photosensitivity. Gratings were formed by exposing the fibre core to a 248 nm KrF laser for 5 minutes with a fluence of 130 mJ/cm2/pulse at a rate of 20 pulses/s.