ti p t

urefringence. In the hybrid MOCS the optical path is embedded in a magneto-optical material, and the fi-bers are used as a communication channel between the transducer and the optoelectronic unit. The ad-vantages of this kind of sensor include its higher Verdet constant and the possibility of removal with-out cutting the electrical conductor. However, there are several drawbacks related to the materials cur-rently used, including optical activity, linear birefrin-gence, and temperature dependence. Several setups have been presented. Triangular1 tallic mirror at the end of the optical path improves current sensitivity thanks to the nonreciprocity of the Faraday effect, and it minimizes the effects of both linear birefringence and optical activity ~reciprocal effect! with respect to the conventional square-shaped transducer.3 It is well known that certain materials act as po-larization rotators when placed in a magnetic field. The orientation of linearly polarized light propagat-ing in such materials suffers a rotation under the influence of that field. This rotation is known as the Faraday effect, which can be described as F 5 V z B, (1) where B is the component of the magnetic flux den-sity in the direction of light propagation and V is the Verdet constant. Materials such as Y2Fe5O12 ~YIG! and Bi12SiO20 ~BSO! are currently used. YIG is a ferromagnetic material with a high Verdet constant, but it has several drawbacks, namely, its strong tem