Single-sized phase-change metasurfaces for dynamic information multiplexing and encryption

Optical metasurfaces empower us to manipulate the electromagnetic space and control light propagation at the nanoscale, offering a powerful tool to achieve modulation of light for information processing and storage. In this paper, we propose a phase-change metasurface to realize dynamic multiplexing and encryption of near-field information. Based on the orientation degeneracy and polarization control governed by Malus's law, we elaborately design the orientation distribution of Sb2S3 meta-atoms with the same dimension to simultaneously satisfy the amplitude modulation requirements of three independent channels. Using the corresponding polarization control as decoding keys, three different nanoprinting images can be displayed, and these multiplexed images can be switched on and off by leveraging the reversible tunability of the Sb2S3 meta-atoms between the amorphous and crystalline states. With the unparalleled advantages of ultracompactness, simple design strategy, high information density and security, the proposed metasurfaces afford promising prospects for high-end applications in ultracompact and intelligent dynamic display, high-dense optical data storage, and optical information encryption. Published by the American Physical Society 2024