  We present several schemes for heralded storage of polarization states of
single photons in single ions, using the calcium-40 ion and photons at 854 nm
wavelength as specific example. We compare the efficiencies of the schemes and
the requirements for their implementation with respect to the preparation of
the initial state of the ion, the absorption process and its analysis. These
schemes may be used to create and herald entanglement of two distant ions
through entanglement swapping; they are easily adapted to other atomic systems
and wavelengths.
