Dynamic Multicolor Upconversion Through Excitation Pulse Duration Modulation toward Machine Learning Assisted Optical Encryption

Laser & Photonics Review, Journal Year: 2025, Volume and Issue: unknown

Published: May 6, 2025

Abstract Optical encryption technology demonstrates significant potential for advanced information security applications due to its inherent advantages in high‐speed operation, multidimensional processing, and parallel computation capabilities. However, current research this field has predominantly focused on elementary optical anti‐counterfeiting techniques binary coding systems, with limited exploration of sophisticated methodologies. In study, a novel strategy is presented that employs NaYF 4 multilayer core–shell nanocrystals enable dynamic full‐color upconversion (UC) emission modulation under single‐wavelength excitation, thereby facilitating high‐capacity through machine learning (ML)‐assisted processing. Through systematic investigation UC photophysical mechanisms, it revealed the tunability originates from both excitation power dependence pulse width sensitivity mediated by rare earth ion cross‐relaxation processes. The rich generated these mechanisms been systematically organized into comprehensive ML‐constructed database, functioning as an “codebook” protocols. developed ML framework exceptional capability identifying subtle signature differences, achieving over 98% recognition accuracy database pattern matching. This system theoretically enables decryption 18 8 distinct patterns. These findings establish new paradigm development provide critical insights advancing next‐generation systems.

Language: Английский

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High-Yb³⁺-Doped NaYbF₄:10% Er@NaYF₄ Alloyed Nanoparticles for Brightening Upconversion and Multi-Colorizing Information Encryption

ACS Applied Optical Materials, Journal Year: 2024, Volume and Issue: 2(4), P. 595 - 603

Published: March 25, 2024

Alloyed upconversion nanoparticles (aUCNPs, NaYbF4:10% Er@NaYF4) with high Yb3+ doping were designed to brighten luminescence, exploring multicolor patterns of information encryption. The luminescence intensity aUCNPs was 2.3 times higher than that common doped UCNPs reported (dUCNPs, NaYF4:20% Yb, 2% Er@NaYF4). Furthermore, because the (90%), both green and red emissions enhanced, ∼4.2 ∼17.2 stronger 10% Er@NaYF4, respectively. reasons for having a brightened explored by synthesizing four different structures comparing their luminescence. These are attributed unique features: (1) larger absorption cross section accumulating energy, (2) more efficient energy transfer between Er3+, (3) inert shell inhibiting surface quenching. Eventually, three colors including yellow, orange, obtained combining neutral (NR) taking advantage inner filter effect (IFE), thus successfully applied in encryption patterns.

Language: Английский

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Dynamic modulation of multicolor upconversion luminescence of Er3+ via excitation pulse width

The Journal of Chemical Physics, Journal Year: 2024, Volume and Issue: 160(20)

Published: May 28, 2024

Lanthanide-doped upconversion (UC) luminescent materials display multicolor emissions, making them ideal for a variety of applications, such as multi-channel biological imaging, fluorescence encryption, anti-counterfeiting, and 3D display. Manipulating the UC emissions with fixed composition is crucial their applications. Herein, we propose facile strategy to achieve pulse-width-dependent in NaYF4:Yb/Er/Tm nanocrystals. Upon excitation 980 nm continuous-wave laser diode, Er3+ ions NaYF4:20%Yb,15%Er,1%Tm nanocrystals exhibited red-to-green (R/G) ratio 11.3. Nevertheless, by employing pulse widths from 0.1 10 ms, R/G can be easily adjusted 0.9 11.3, resulting continuous remarkable color transformation green, yellow, orange, red. By virtue dynamic luminescence variation these nanocrystals, demonstrated potential applications areas anti-counterfeiting information encryption. These findings provide deep insights into excited-state dynamics energy transfer upon excitation, which may pave way designing toward versatile

Language: Английский

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Manipulating energy migration in nanoparticles toward tunable photochromic upconversion

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Dec. 30, 2024

Smart control of energy interactions plays a key role in manipulating upconversion dynamics and tuning emission colors for lanthanide-doped materials. However, quantifying the flux particular migration representative sensitizer-activator coupled system has remained challenge. Here we report conceptual model to examine single nanoparticle by designing an interfacial transfer mediated nanostructure. We show that indeed occurs simultaneously with competition between them can be quantified proposing characteristic ratio parameter. Moreover, this is also able realize color-switchable photochromic temporal up-transition processes. These findings offer deep insight into understanding provide versatile approach nanostructures tunable colors, showing great promise applications logic operation information security.

Language: Английский

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Tm³⁺ mediated multicolor luminescence of NaYbF₄:Er,Tm@NaYF₄ for advanced anti-counterfeiting

Dalton Transactions, Journal Year: 2024, Volume and Issue: 53(22), P. 9380 - 9386

Published: Jan. 1, 2024

NaYbF 4 :Er,Tm@NaYF UCNPs combine the advantages of Tm 3+ mediated multicolor luminescence and excitation power dependent color change, showing great application potential in advanced anti-counterfeiting paintings.

Language: Английский

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Er³⁺-Sensitized Upconversion/Down-Shifting Luminescence in Metal–Organic Frameworks

The Journal of Physical Chemistry Letters, Journal Year: 2023, Volume and Issue: 14(47), P. 10624 - 10629

Published: Nov. 20, 2023

Photoluminescent metal–organic frameworks (MOFs) are used as optical materials with excellent properties, of which the lanthanide-doped MOFs able to emit in a broad region from visible near-infrared due their unique 4f-orbital electronic structure. Herein, Er3+ and Y3+ ions selected metal centers is sensitizer absorb 980 nm excitation light. At same time, also act activators that upconverting light down-shifting In addition, Tm3+, Ho3+, Eu3+ were individually doped into Er3+-doped investigate variation energy-transfer paths presence different lanthanide activators. Finally, pathway energy transfer these Er3+-sensitized luminescent-MOFs was summarized. This work provides new insights for further development both upconversion luminescence MOFs.

Language: Английский

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Investigation of Upconversion Luminescence Attenuation in Aqueous Solutions Under 980 nm and 808 nm Irradiation

Journal of Analysis and Testing, Journal Year: 2023, Volume and Issue: 7(4), P. 377 - 383

Published: Dec. 1, 2023

Language: Английский

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Achieving visual information encryption employing the asymmetric principle through programmable and challenging-to-clone multicolor-tunable luminescence

Materials Today Physics, Journal Year: 2024, Volume and Issue: 41, P. 101350 - 101350

Published: Feb. 1, 2024

Language: Английский

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Excitation power-dependent multicolor upconversion in NaLnF₄:Er³⁺ under 1532 nm irradiation for anti-counterfeiting application

Optics Letters, Journal Year: 2024, Volume and Issue: 49(11), P. 2978 - 2978

Published: May 8, 2024

Upconversion (UC) materials are renowned for their ability to convert low-energy photons into high-energy ones. The manipulation of parameters allows the observation multicolored UC luminescence (UCL) within a single material system. While modulation UCL commonly relies on excitation at approximately 980 nm, investigation activated by 1532 nm source remains comparatively scarce. In this work, we introduce NaLnF 4 :Er 3+ as novel class smart luminescent materials. When power density laser increases from 0.5 20.0 W/cm 2 , emission peak positions remain unchanged, but red-to-green (R/G) ratio decreases significantly 18.82 1.48, inducing color shift red yellow and ultimately green. contrast, no variation is observed when excited with different densities. This power-dependent can be attributed competitive processes upward pumping downward relaxation electrons I 9/2 level Er . By utilizing unique characteristics its potential utility in anti-counterfeiting applications demonstrated. Our research highlights distinctive optical properties provides insights use technologies.

Language: Английский

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Understanding of Lanthanide-Doped Core–Shell Structure at the Nanoscale Level

Nanomaterials, Journal Year: 2024, Volume and Issue: 14(12), P. 1063 - 1063

Published: June 20, 2024

The groundbreaking development of lanthanide-doped core–shell nanostructures have successfully achieved precise optical tuning rare-earth nanocrystals, leading to significant improvements in energy transfer efficiency and facilitating multifunctional integration. Exploring the atomic-level structural, physical, properties nanocrystals is essential for advancing our understanding their fundamental principles driving emerging applications. However, knowledge structural details nanocrystal structures remains limited. This review provides a comprehensive discussion synthesis strategies, characterization techniques, interfacial ion-mixing phenomena, strain effects, spectral modulation rare-earth-doped nanocrystals. Additionally, we prospectively discuss challenges encountered studying fine particularly increasing demand researchers integrate interdisciplinary utilize high-end precision instruments.

Language: Английский

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