Directional emission from dye-functionalized plasmonic DNA superlattice microcavities
Directional emission from dye-functionalized plasmonic DNA superlattice microcavities
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DOI：
10.1073/pnas.1619802114
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发表时间：
2017-01-17
影响因子：
11.1
通讯作者：
Mirkin, Chad A.
中科院分区：
文献类型：
--
作者：
Park, Daniel J.;Ku, Jessie C.;Mirkin, Chad A.
三维等离子体超晶格微腔，由可编程的原子等价物，包括与DNA功能化的金纳米粒子制成，被用作研究定向光发射的测试平台。DNA引导的纳米颗粒胶体结晶允许形成微米级单晶体心立方金纳米颗粒超晶格，其中染料分子以菱形十二面体的形式偶联到将颗粒连接在一起的DNA链。在二氧化硅中的封装允许创建具有固定在空间中的等离子体激元活性颗粒和染料分子的稳健架构。在微米尺度下，各向异性的菱形十二面体晶体习性与光子模式耦合以给出定向光发射。在纳米尺度下，染料偶极子和表面等离子体之间的相互作用可以通过将染料分子偶联到DNA颗粒-连接链的特定位点来微调，从而调节染料-纳米颗粒距离（研究了三个不同的位置）。以亚纳米精度控制染料位置的能力允许系统地调整等离子体激元相互作用强度和衰减寿命，其结果已得到跨越从纳米到微米的长度尺度的电动力学计算的支持。控制表面等离子体激元/激子相互作用在这种超晶格微腔的独特能力将催化涉及量子光学，等离子体激元激光物理，强耦合和非线性现象的研究。
Three-dimensional plasmonic superlattice microcavities, made from programmable atom equivalents comprising gold nanoparticles functionalized with DNA, are used as a testbed to study directional light emission. DNA-guided nanoparticle colloidal crystallization allows for the formation of micrometer-scale single-crystal body-centered cubic gold nanoparticle superlattices, with dye molecules coupled to the DNA strands that link the particles together, in the form of a rhombic dodecahedron. Encapsulation in silica allows one to create robust architectures with the plasmonically active particles and dye molecules fixed in space. At the micrometer scale, the anisotropic rhombic dodecahedron crystal habit couples with photonic modes to give directional light emission. At the nanoscale, the interaction between the dye dipoles and surface plasmons can be finely tuned by coupling the dye molecules to specific sites of the DNA particle-linker strands, thereby modulating dye-nanoparticle distance (three different positions are studied). The ability to control dye position with subnanometer precision allows one to systematically tune plasmon-excition interaction strength and decay lifetime, the results of which have been supported by electrodynamics calculations that span length scales from nanometers to micrometers. The unique ability to control surface plasmon/exciton interactions within such superlattice microcavities will catalyze studies involving quantum optics, plasmon laser physics, strong coupling, and nonlinear phenomena.