Nonvolatile plasmonic holographic memory based on photo-driven ion migration

Stability of data storage is essential for optical information processing. TiO2 nanoporous films loaded with smallsized Ag nanoparticles thus attracted much attention due to their fast and polarization-sensitive photochemical response, which is able to realize optical phase modulation and high-density optical memory. However, little attention was given to the modulation of the silver ion migration, which plays a key role in anti-erasure of the recorded hologram. In this paper, the strong coupling of two phase gratings was achieved by long-term recording in the Ag-TiO2 film irradiated with a pair of coherent left-and right-hand circular polarization lights from a Blu-ray (similar to 405 nm) laser. The migration of Ag+ ions was enhanced by the electronic field gradient force. A stable polarization holographic grating was obtained by this method and observed by a polarizing microscope. This work provided a strategy for a nonvolatile device based on photo-driven ion migration. (C) 2017 Optical Society of America