Spatial mode effects in a cavity EIT-based quantum memory with ion Coulomb crystals

Quantum storage and retrieval of light in ion Coulomb crystals using cavity electromagnetically induced transparency is investigated theoretically. It is found that, when both the control and probe fields are coupled to the same cavity mode, their transverse mode profile affects the quantum memory efficiency in a non-trivial way. Under such conditions the control field parameters and crystal dimensions that maximize the memory efficiency are calculated.