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

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. © 2013 Elsevier Ltd.This work was supported in part by Ministerio de Economía y Competitividad through project TEC2011-27314. Javier Nuño acknowledges funding from the Ministerio de Ciencia e Innovación through an FPI fellowship.Peer Reviewe