Accelerated formation of persistent holographic gratings based on one-directional electron transfer in KCl-Ag/Ta2O5 nanocomposites

Abstract

Permanent preservation of data is essential for massive information recording. Combination of semiconductor with plasmonic nanoparticles has been applied in multicolor display and high-density optical storage. However, bidirectional electron transfer occurs at the Schottky interface under UVA irradiation, resulting in reversible photochemical reaction, information erasure, low recording efficiency and writing rate. To address these issues, a novel Schottky heterostructure of Ag/Ta2O5 modified with alkali halide is developed to realize photoinduced one-directional electron transfer from metal to semiconductor. The recorded information in such a medium of KCl-Ag/Ta2O5 presents excellent holographic storage stability even under exposure of a strong UVA ray (360 nm, 385 mW/cm(2)). Meanwhile, grating growth rate and efficiency are significantly enhanced by optimizing Ag particle distance and Cl- anion loading amount. This work provides an important strategy for fast and persistent data storage. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement