In this talk, I will discuss how gravitational waves of low frequency perturb the electromagnetic modes in step-index optical fibres. After reviewing previous analyses of non-inertial effects in fibre-optic waveguides, I will discuss how weak gravitational waves alter Maxwell’s equations for linear dielectrics. Solving these equations perturbatively (with boundary conditions appropriate to describe single-mode optical fibres) leads to explicit results for the first order correction of the fibre modes. In particular, I will discuss the perturbation of the phase and polarisation of light in such waveguides.
