Alain Kung, Pierre -A. Nicati, Philippe A. Robert

Swiss Federal Institute of Technology (EPFL), Metrology Laboratory, CH-1015 Lausanne, Switzerland

(Received July 1, 1996; Accepted September 9, 1996)

A novel reciprocal Brillouin fiber optic current sensor has been developed and tested. The sensor is based on two counter-propagating Brillouin lasers circulating in a fiber ring cavity. It shows a sensitivity of 126 Hz/A that is very close to the maximum sensitivity obtained by using fibers without linear birefringence. The limitations due to the Kerr effect and optical feedbacks in the system are also investigated.

Key words : stimulated Brillouin scattering (SBS), fiber ring resonator, current sensor, Kerr effect