Laser‐Splashed Plasmonic Nanocrater for Ratiometric Upconversion Regulation and Encryption

Abstract

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adom.201900610. Upconversion NanoparticlesOptical multiplexing and encoding based on light-matter interactions in physical dimensions such as polarization, [1][2][3] wavelength, [4][5][6] angular dispersion, [7][8][9] and orbital angular momentum [10][11][12] have been well heralded as an enabling platform for high-security encryption applications in banknotes, ID cards, and so on. [13,14] Among these well-developed optical

Geometry-Programmable Perovskite Microlaser Patterns for Two-Dimensional Optical Encryption

“…Data storage and information security technologies have drawn considerable attention due to their widely applications ranging from economic and military fields to our daily uses. − Owing to its fast readability and large storage capacity, two-dimensional (2D) luminescent patterns with luminescent materials arranged in both vertical and horizontal sequences are considered as promising platforms to construct optical recording devices and confidential tags. − Nevertheless, most 2D luminescent patterns based on traditional luminophores can only provide broadband photoluminescence (PL) emissions, which usually overlap with each other, thus making it difficult to tell them apart and resulting in a relatively limited security level . A faithful strategy to increase the information density and security level of such devices is the utilization of smart luminescent materials with reversible changes of emission properties to external stimuli, which could effectively prevent the information or data from being forged. − However, those externally applied stimuli would inevitably degrade the luminescent performances during the encryption and decryption cycles, which significantly hinder their practical applications.…”

Surface Plasmon–Photon Coupling in Lanthanide-Doped Nanoparticles

“…The same consideration has also been extended to nanohybrids comprising nanocavities and UCNPs. When the fundamental mode of a nanocavity resonates with the lanthanide emission, researchers generally ascribe enhanced emission intensity and fast radiative decay rate to the Purcell effect. ,− …”

“…Apart from boosting emission at a particular wavelength, it is possible to tune intensity ratios in a single set of UCNPs through structural engineering. For illustration, two sets of red-to-green ratios were detected simultaneously in NaYF 4 :Yb/Ho/Ce nanocrystals under NIR irradiation when dispersed onto a specific sliver slab containing two types of nanocraters with different morphologies (Figures f and a) . For nanogaps formed between nanocubes and a substrate, its fundamental resonance mode can be subtly adjusted by varying the size of metal nanocubes.…”

Super-Resolution Imaging With Lanthanide Luminescent Nanocrystals: Progress and Prospect

“…Therefore, effective approaches to greatly shorten the luminescence lifetime to a sub-microsecond level, and in the meantime reserve or enhance the emission intensity, is mightily desired to ensure brief pixel dwell times. Several methods including elevating the doping concentration of sensitizer Yb 3+ and coupling gap plasmonic cavity are proposed ( Su et al, 2017 ; Feng et al, 2019 ). So far, ultrabright spontaneous emission of Er 3+ with ultrashort luminescence lifetimes (1.4 µs) has been realized through a finely designed nanocavity, where the nanostructures should be elaborately and specifically fabricated, leading to an inevitable obstacle for the freewheeling targeting distribution of the luminescence center on bio-specimens ( Wu et al, 2019 ; Xu et al, 2021 ).…”