Recording arbitrary polarization states on photorefractive media

We propose a new recording scheme by which arbitrary polarization states are stored in volumetric and polarization insensitive photorefractive materials. In the scheme, Stokes parameters of an arbitrary polarization state are recorded as grating strength by using the relation between the interference intensity in recording process and the diffraction efficiency in reading process. We show the experimental setup to retrieve linear, circular, and elliptic polarization states using a typical non-polarization dependent photorefractive media, an iron-doped lithium niobate crystal. The polarization state introduces an additional degree of freedom for storing information, and is useful for expanding the capacity in holographic data storage.