Reduction of nonreciprocity noise in wound fiber optic interferometers

Nonreciprocity caused by temperature-rate-induced phase bias in fiber optic interferometers is experimentally investigated. A series of temperature ramp rates is applied to several fiber optic test coils to produce time-varying thermal gradients along the axial and radial directions. Data on the induced peak rate are presented for coils wound using the conventional (end-to-end) wind and the quadrupolar (center-to-end) wind. The quadrupolar-wound coil exhibits substantially lower sensitivity to temperature transients. It is found that the conventional wind can be considered for low-perlormance, low-cost systems operating in moderately adverse environments.