Reducing group delay spread using uniform long-period gratings

Long Period Fibre Gratings

Long-period gratings in wavelength-scale microfibers.

We report the fabrication of long-period gratings (LPGs) in wavelength-scale microfibers with diameters from 1.5 to 3 microm. The LPGs were fabricated by use of a femtosecond IR laser to periodically modify the surface of the fibers. These LPGs have grating periods of a few tens of micrometers, much smaller than those in conventional optical fibers. A compact 10-period LPG with a device length ...

Differential Group Delay Analysis of Uniform Bragg Gratings Written in Hi-Bi Optical Fibers

Fibre Bragg Gratings (FBG) have become key components in optical communications systems, and, in the same time, lightwave transmissions are more intolerant to the polarization mode dispersion. Consequently, the polarization properties of FBG are of paramount importance. In this frame, we analyze the wavelength dependency of Differential Group Delay in the particular case of a uniform Bragg Grat...

Multiplexed long period gratings with differential interrogation

Tunable nanophotonic delay lines using linearly chirped contradirectional couplers with uniform Bragg gratings.

We demonstrate an integrated tunable optical delay line in grating-assisted contradirectional couplers using a CMOS-compatible photonic technology. The input signal is delayed through dispersive Bragg gratings and distributedly coupled to the drop port of the coupler without backreflections. This add-drop design enables monolithic integration of grating-based delay lines without using optical c...