It has recently been shown1 that high power superluminescent sources such as required for the fiber optic gyro and other sensor applications have an excess noise component which prevents the SNR from increasing beyond a fixed value. The excess noise is inherent in the thermal nature of the light and will always be present for thermal type sources. Since with the higher power sources now available the excess noise can be considerably larger than the fundamental shot noise limit, the question arises whether this type of noise can be eliminated using a form of compensation. Such a scheme requires the noise to be correlated on two detectors.
© 1990 Optical Society of AmericaPDF Article