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Updated: Jun 20, 2026

A Random-displacement Measurement by Combining a Magnetic Scale and Two Fiber Bragg Gratings
Published on: September 30, 2019
Observation of intensity-induced nonreciprocity in a fiber-optic gyroscope
Abstract:
Nonreciprocal phase shift has been predicted and observed in a fiber-optic gyroscope based on a Sagnac interferometer when the intensities of the counterpropagating beams are unequal. The magnitude of this intensity-induced phase shift is 1.4 rad/W power difference. At 1-microW power difference, this is equivalent to a rotation rate of 0.2 degrees /h in our 200-m-long fiber with a core radius of 2.25 microm that is wound around a spool of 19-cm diameter. The data are consistent with theoretical predictions based on four-wave mixing in the quartz fiber.
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