Rewritable Optical Memory Through High-Registry Orthogonal Upconversion

Kezhi Zheng; Sanyang Han; Xiao Zeng; Yiming Wu; Shuyan Song; Hongjie Zhang; Xiaogang Liu

doi:10.1002/adma.201801726

Rewritable Optical Memory Through High-Registry Orthogonal Upconversion

Adv Mater. 2018 Jul;30(30):e1801726. doi: 10.1002/adma.201801726. Epub 2018 Jun 11.

Authors

Kezhi Zheng^{1

2}, Sanyang Han¹, Xiao Zeng¹, Yiming Wu¹, Shuyan Song³, Hongjie Zhang³, Xiaogang Liu^{1

4}

Affiliations

¹ Department of Chemistry, National University of Singapore, Singapore, 117543, Singapore.
² State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, 130012, China.
³ State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China.
⁴ Center for Functional Materials, National University of Singapore Suzhou Research Institute, Suzhou, Jiangsu, 215123, China.

PMID: 29889322
DOI: 10.1002/adma.201801726

Abstract

An experimental design, based on a combination of core-shell-structured upconversion nanoparticles and diarylethene photochromic molecules, for achieving rewritable optical memory is reported. This core-shell design enables the nanoparticles to emit two sets of distinct emission bands with ultrahigh spectral purity through laser excitation at 980 and 1532 nm. Importantly, the ultraviolet emission of the nanoparticles under 980 nm irradiation is used to activate the cyclization reaction of diarylethene through CC bond formation, while the green emission from the nanoparticles upon 1532 nm excitation leads to the cleavage of the newly formed CC bond. This pathway offers a convenient and versatile optical method for controlling the process of data writing and erasing with high spatiotemporal resolution.

Keywords: cyclization reaction; high spectral purity; optical memory; orthogonal upconversion; reversible photoswitching.