Electron beam direct-write tunable polymeric waveguide grating filter

We report a tunable electron beam direct-write polymeric waveguide Bragg grating filter based on a negative tone epoxy, The waveguide filter, with a 5-mm-long first-order grating, exhibits a transmission peak of -27 dB and a 3dB bandwidth of ~0.8 nm, and there is an excellent agreement between experimental data and simulation results. The temperature response of the filter is also characterized. The rate of change of refractive index dn/dT is ~-1.8 * 10/sup -4/C at 1550-nm wavelength for both transverse electric and transverse magnetic polarizations, and the rate of change of peak wavelength d(lambda)/dT is~-0.14 nm/C. The tuning performance is comparable to other grating devices fabricated using multiple processing steps.