Photorefractive polymers with non-destructive readout

Photorefractive polymers are suitable for real-time holographic applications. Since the recording and readout of a hologram is carried out with laser beams with the same wavelength, the readout process partially erases the stored information, a problem common to all current photorefractive materials and referred to as destructive readout. In this paper we describe photorefractive polymers that are sensitized by two-photon absorption. Holographic recording is achieved with high-intensity writing beams and readout using low light intensity, but high power beams. Using this nonlinear recording scheme, non-destructive readout was demonstrated.