Source statistics and the Kerr effect in fiber-optic gyroscopes.

We show theoretically that polarized thermal light as generated by a superluminescent diode has the properties required to compensate for Kerr-effect drift in fiber gyroscopes. Light from some multimode lasers has related properties that can substantially reduce Kerr-effect errors. An experimental gyroscope using a multimode laser diode demonstrates no Kerr-effect error and provides significantly improved long-term stability.