基于单颗粒微米核壳晶体的微区上转换发射光谱构筑微纳光子学条形码  

Constructing micro/nano-photonics barcodes based on micro-region upconversion emission spectrum of single core-shell microcrystal

作　　者：高伟 张正宇 张景蕾 丁鹏 韩庆艳 张成云 严学文 董军 Gao Wei;Zhang Zheng-Yu;Zhang Jing-Lei;Ding Peng;Han Qing-Yan;Zhang Cheng-Yun;Yan Xue-Wen;Dong Jun(School of Electronic Engineering,Xi’an University of Posts and Telecommunications,Xi’an 710121,China)

机构地区：[1]西安邮电大学电子工程学院,西安710121

出　　处：《物理学报》2024年第18期162-172,共11页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12274341);陕西省基础科学研究项目(批准号:23JSY007);陕西省重点研发计划(批准号:2023-YBGY-256);陕西省自然基金重点项目(批准号:2022JZ-05);陕西省自然科学基金青年科学基金(批准号:2022JQ-041);陕西省教育厅服务地方专项计划(批准号:22JC-057);西安市高校院所人才服务企业项目(批准号:23GXFW0089)资助的课题。

摘　　要：基于外延生长技术构建不同结构特性的核壳结构已成为调控稀土掺杂微纳晶体材料发光特性的有效技术手段之一.为此,本文基于多次外延生长并引入NaYF_(4)中间隔离层,构建了具有壳层独立发光特性NaYF_(4):50%Yb^(3+)/2%Tm^(3+)@NaYF_(4)@NaYF_(4):20%Yb^(3+)/2%Er^(3+)@NaYF_(4)@NaYbF_(4):2%Er^(3+)多层微米核壳晶体.在980 nm激光激发下,借助共聚焦显微光谱测试系统,通过改变单颗粒微米晶体的激发位置,研究了单颗粒核壳微米晶体不同微区内的发光和能量传递特性.实验结果表明:在相邻发光层之间引入NaYF_(4)惰性壳,不仅可实现单颗粒微米晶体区域内发光的调控,且可有效抑制了各壳层离子间的相互作用,实现了各壳层的多彩独立发射.同时,基于单颗粒核壳微米晶体不同区域内多彩发射特性,构建具有信息可调的微纳光子学条形码.由此可见,本文所构建具有区域化可调发射的微米核壳结构,可在不同的激发条件下实现其发光的多彩可调,其丰富光谱指纹信息为单颗粒微米材料在光学防伪领域中的应用提供了新的途径.The construction of core-shell structures with different structural properties based on the epitaxial growth technique has become an effective technique for regulating the luminescence properties of micro/nanocrystals.In order to obtain richer spectral information,NaYF_(4):50%Yb^(3+)/2%Tm^(3+)@NaYF_(4)@NaYF_(4):20%Yb^(3+)/2%Er^(3+)@NaYF_(4)@NaYbF_(4):2%Er^(3+)multilayered core-shell microcrystals are prepared by using multiple epitaxial growth through introducing surface modifiers and controlling their reaction conditions.The XRD and SEM results clearly show that the core-shell microcrystals possess a pure hexagonal crystal structure in the form of a disk.The microdesk has a thickness of about 2.32μm and a diameter of about 28.31μm.The upconversion luminescence characteristics of different single microcrystal structures are investigated by a confocal microspectroscopy system.In order to realize the selective excitation and emission of a single microcrystal,the spatial distribution of luminescent ions can be controlled through introducing an intermediate isolation layer.Under 980 nm laser excitation,different excitation sites of the single microdisk exhibit different upconversion emission characteristics.The significant blue(450 and 475 nm),red(648 nm)and green(524 and 540 nm)emissions are observed,which mainly originat from Tm^(3+)and Er^(3+)radiative transitions.Meanwhile,the red and blue upconversion emission intensities of the microcrystals are improved by using various shell layers.In addition,the luminescence and energy-transfer features of single microcrystals are explored by changing the excitation position.The experimental results demonstrate that the incorporation of NaYF_(4)inert shells between luminescent layers can regulate luminescence and prevent ions from interacting.By utilizing the spectral fingerprint data of dopant ions in various shell layers,we create customizable micro-nano photonic barcodes and employ them for optical anti-counterfeiting detection.This study explores the use of constructe

关 键 词：上转换发光 微米核壳晶体 单颗粒 发光调控 光子学条形码 

分 类 号：O482.31[理学—固体物理]