Fiber Sagnac interferometers with ultralong and random distributed feedback Raman laser amplification

•We study the application of ultralong lasers to fiber optic gyroscope sensors.•The performance limitations of such devices are studied.•According to the results, a 5-fold increase in sensitivity is possible.

We numerically study and compare the performance limitations imposed by accumulated noise and nonlinear phase difference in various configurations of amplified fiber optic gyroscopes in which amplification is provided by stimulated Raman scattering, with a focus on ultralong and random distributed feedback Raman fiber lasers. We show that, even in the presence of pump power and signal instabilities, some of the proposed configurations have the potential to allow the use of up to 5 times longer spool lengths, with a corresponding 5-fold increase in sensitivity. The results could have direct application to the improvement of the detection of seismic rotational events.