NARROW BANDWIDTH VOLUME HOLOGRAPHIC OPTICAL FILTER OPERATING AT THE KR TRANSITION AT 1547.82-NM

We describe and characterize a narrow bandwidth volume holographic optical filter operating at the Krypton transition line (1s2-2p8) at 1547.82 nm, which corresponds to the center wavelength of the proposed International Telecommunications Union wavelength standard. A reflectivity of 98% and a bandwidth full width at half-maximum of 0.18 nm are measured. The filter exhibits clean sideholes with a -20 dB optical response 0.5 nm away from the peak. The filter can be fabricated and operated with an absolute wavelength precision better than 0.005 nm.