Optical Kerr effect in long fibers.

Optical Kerr modulation of >100% is demonstrated in long birefringent optical fibers using low laser powers of ~1 W. We have experimentally investigated the effects of group-velocity dispersion, thermal stability of polarization, and fiber birefringence. Use of fiber Kerr modulation as a fast optical shutter is studied, and it is concluded that resolution times shorter than 1 psec are possible in principle.