Key points are not available for this paper at this time.
To measure currents on high-voltage lines, the Faraday rotation is used in a single-mode optical fiber encircling the conductor. Disturbing linear birefringence is suppressed by twisting the fiber. With ∼10 m of fiber, coiled with a 3-cm radius, we obtain 0.25 mrad/A polarization rotation, permitting measurement of currents of 0.2–2000 A.
Rashleigh et al. (1979) studied this question.