Abstract: An apparatus and method for sensing current. The apparatus includes an optical fiber having first and second opposing ends, a recirculator configured such that when light propagates from the respective first and second ends of the optical fiber, at least some of the light is reflected, directed or passed by the recirculator into the respective opposing ends of the optical fiber to propagate through the optical fiber and form an optical loop having an opening there through.

Abstract: An apparatus for sensing current and a method for sensing current are provided. The apparatus includes an optical fiber having first and second opposing ends and a hollow passageway therethrough, a recirculator configured such that when light propagates from the respective first and second ends of the optical fiber, at least some of the light is reflected by the recirculator into the respective opposing ends of the optical fiber to propagate through the optical fiber and form an optical loop having an opening therethrough, and a Faraday sensitive material positioned in the optical loop such that the light passes therethrough, an index of refraction of the Faraday sensitive material changes when a current flows through the opening of the optical loop.

Abstract: An apparatus for sensing current and a method for sensing current are provided. The apparatus includes an optical fiber having first and second opposing ends and a hollow passageway therethrough, a recirculator configured such that when light propagates from the respective first and second ends of the optical fiber, at least some of the light is reflected by the recirculator into the respective opposing ends of the optical fiber to propagate through the optical fiber and form an optical loop having an opening therethrough, and a Faraday sensitive material positioned in the optical loop such that the light passes therethrough, an index of refraction of the Faraday sensitive material changes when a current flows through the opening of the optical loop.