Dynamics of electrically polarized magnetic monopoles in spin ice

We propose a simple mechanism through which elementary excitations in spin ice, namely, magnetic monopoles, lead to spontaneous macroscopic electric polarization by breaking the space inversion symmetry in the spin configuration. We show that while the magnetic monopole charge is conserved in hopping, the corresponding electric dipole moment cannot be a constant of motion. The possibilities as well as the limitations involved in electrical manipulation of the monopole dynamics are also discussed.