I. A. Andronova

Effects of polarization nonreciprocity in fiber ring interferometers

The criteria, distinguishing reciprocal media from nonreciprocal media are well known. However, with the development of fiber ring interferometry, effects of phase nonreciprocity caused by polarization effects, have been found in media, which are reciprocal in the traditional meaning. The polarization effects occur when waves, which have been equally polarized at the input, become differently polarized after passing through a fiber ring interferometer in counter directions. There are some papers, which provide calculations and results of experiments on the effects of polarization nonreciprocity for concrete schemes. The aim of the present work is to summarize the known results, and to analyze the effects of polarization nonreciprocity based on the general Jones matrix of FRI, which satisfies the well- known criterion of reciprocity.

All-fiber optical gyroscopes on orthogonal polarizations

The expressions for the nonreciprocal phase at the output of a fiber ring interferometer (FRI) related to polarization phenomena are obtained in the general form. These expressions are used to analyze two systems of the FRIs on anisotropic elements without polarizer with one and two beam splitters with allowance for their phase anisotropy and losses. We formulate the requirements on the elements of circuits and their adjustment, which lead to minimization of the nonreciprocal polarization phase due to the single-loop realization of two independent orthogonal gyroscopic channels whose signals are added at the output. This allows us to use the above simple circuits for creating moderate-accuracy fiber gyroscopes.

Influence of anisotropy and losses in beam splitters on the output characteristics of fiber ring interferometers

We consider the influence of phase characteristics of a beam splitter on the output signal of fiber ring interferometer (FRI). The relation between energy losses in the beam splitter and its phase characteristics is established. Allowing for these characteristics, we obtain expressions for the spurious signal at the FRI output, which differ from the known formulas, and consider methods for decreasing its value and drift.