Rocking filter formation in photosensitive high birefringence optical fibres

Parent et al. observed that the refractive index changes induced in optical fibres by Hill grating formation (at 488 and 514.5 nm) were birefringent. A wavelength filter, formed in a simple and novel way by exposing high birefringence fibre to linearly polarised 488nm light, is reported. Narrow bandwidth operation and high conversion efficiencies are achieved experimentally between the two orthogonal polarisation states of the fibre.