The phase delay of the fundamental LP01 mode in a single-mode optical fiber is studied using periodic perturbation of the fiber axis. A large phase shift may be obtained through distortion-induced birefringence, with less than 1.5- dB coupling loss to the radiative modes.
© 1987 Optical Society of America
H. Grebel, "Phase delay of coupled modes in single-mode optical fibers," Opt. Lett. 12, 735-737 (1987)