Polymeric long-period waveguide gratings

A long-period waveguide grating (LPWG) was demonstrated in a polymeric waveguide fabricated on an SiO/sub 2/-Si substrate using standard cleanroom fabrication processes: ultraviolet photolithography and reactive ion etching. Experimental results confirm that the relationship between the transmission peak wavelength and the grating period is linear. The LPWG exhibits a maximum attenuation of -18 dB, a minimum 3-dB bandwidth of 6 nm, and the grating length can be as short as 1 cm. The temperature characteristic d(lambda)/dT of the LPWG was also investigated, and is found to be similar to that of long-period fiber gratings.