Polarized Single-Particle Quantum Dot Emitters through Programmable Cluster Assembly

Abstract

Although fluorescence and lifetimes of nanoscale emitters can be manipulated by plasmonic materials, it is harder to control polarization due to strict requirements on emitter environments. An ability to engineer 3D nanoarchitectures with nanoscale precision is needed for controlled polarization of nanoscale emitters. Here, we show that prescribed 3D heterocluster architectures with polarized emission can be successfully assembled from nanoscale fluorescent emitters and metallic nanoparticles using DNA-based self-assembly methods. An octahedral DNA origami frame serves as a programmable scaffold for heterogeneous nanoparticle assembly into prescribed clusters. Internal space and external connections of the frames are programmed to coordinate spherical quantum dots (QDs) and gold nanoparticles (AuNPs) into heterocluster architectures through site-specific DNA encodings. We demonstrate and characterize assembly of these architectures using in situ and ex situ structural methods. These cluster nanodevices exhibit polarized light emission with a plasmon-induced dipole along the QD-AuNP nanocluster axis, as observed by singlecluster optical probing. Moreover, emittance properties can be tuned via cluster design. Through a systematic study, we analyzed and established the correlation between cluster architecture, cluster orientation, and polarized emission at a single-emitter level. Excellent correspondence between the optical behavior of these clusters and theoretical predictions was observed. This approach provides the basis for rational creation of single-emitter 3D nanodevices with controllable polarization output using a highly customizable DNA assembly platform.

Resilient three-dimensional ordered architectures assembled from nanoparticles by DNA

“…For example, a comprehensive strategy for the assembly of designed NP lattices using polyhedral DNA origami constructs of different shapes (26)(27)(28)(29) and particles of different geometries (30,31) for the forma tion of diverse types of lattice symmetries has been demonstrated. Given the exquisite structural control offered by DNA in creating complex 3D structures with integrated functional nanoobjects (13,16,(32)(33)(34)(35), it is increasingly important to have the ability to translate the assembly methodology into a generation of materials that are not limited by the environmental requirements of DNA. For instance, stabilization of DNA structures using polymers and peptoids for a range of buffer conditions was demonstrated (36,37) as a method for preserving DNA structures in a broader range of liquid environments.…”

DNA‐Based Plasmonic Heterogeneous Nanostructures: Building, Optical Responses, and Bioapplications

“…However, by locating QDs at the intersection of two plasmonic metal NPs based on DNA templates, PL enhancement and polarized light emission were obtained at optimized distances. [52,66] The underlying luminescence enhancement mechanism was mainly attributed to the increased excitation rates under enhanced local fields. By controlling the gap to 5 nm, plasmonic Au NP-QD-Au NP antennas and Ag NP-QD-Ag NP antennas showed a 30-fold PL enhancement compared to QDs, attributed to plasmonic coupling and Purcell enhancement.…”

“…[ 10 ] QD–Au NP heterostructures with QDs located in the center of octahedral DNA origami emitted polarized light. [ 52 ] The number and size of assembled Au NPs could be controlled, which affected the polarized light through plasmon‐induced dipoles. Rigid DNA origami allowed the precise control of the interparticle distances and assemblies with different shapes.…”

“…[ 66 ] The SPR of plasmonic Au NPs increased the excitation of a polarization‐dependent electric field and enhanced the PL enhancement factor. [ 52 ] Increasing the sizes of Au NPs and decreasing the interparticle distances between QDs and Au NPs, the PL enhancement factor and detectable polar activity were enhanced. Plasmon‐enhanced PL can be achieved by locating fluorophores at the junction between plasmonic cores and shells.…”

DNA-assembled superconducting 3D nanoscale architectures

“…These staple strands bind the long strand in predetermined places, resulting in the formation of a pre-defined nanoscale structures. DNA origami nanostructures are addressable with nanometer precision, making them suitable for building precise organization of functional materials with optical, magnetic and catalytic functions [24][25][26][27][28] . Recently, approaches for creating designed 3D superlattices from 3D DNA origami frames and nanoparticles of different kinds were demonstrated 9,17 .…”