Methods for Eliminating the Influence of Nonlinear Kerr Effect on the Zero Drift of Fiber Ring Interferometers

摘要

Nonlinear Kerr effect leads to the appearance of a periodic structure in the saturated refractive index of an optical fiber, which corresponds to a standing structure formed by counterpropagating waves in the circuit of a fiber ring interferometer (FRI). If the intensities of counterpropagating waves are slightly different, their reflection from this periodic structure leads to the appearance of a phase shift of interference of counterpropagating waves unrelated to rotation at the FRI output. If a nonmonochromatic radiation source is used in the FRI system, only radiation rereflected from the middle of the circuit makes a contribution to the phase shift. A method for eliminating the influence of the nonlinear Kerr effect on the zero shift of fiber ring interferometers is proposed. This consists in making the middle of the circuit discontinuous. Numerical estimates are made.