Low-power fault-tolerant laser-to-fiber coupling with photorefractive BaTiO(3)

A novel device for low-power fault-tolerant laser-to-fiber coupling is described; it makes use of self-pumped phase conjugation in photorefractive BaTiO(3). We found the degree of fault tolerance to improve by 2 orders of magnitude to 0.02 dB per 100-mum displacement within the determined displacement range at intensities incident on the crystal as low as 2 mW, compared with the losses without the BaTiO(3) present.