title: Plasmonic Toroidal Metamolecules Assembled by DNA Origami.
abstract: We show hierarchical assembly of plasmonic toroidal metamolecules that exhibit tailored optical activity in the visible spectral range. Each metamolecule consists of four identical origami-templated helical building blocks. Such toroidal metamolecules show a stronger chiroptical response than monomers and dimers of the helical building blocks. Enantiomers of the plasmonic structures yield opposite circular dichroism spectra. Experimental results agree well with the theoretical simulations. We also show that given the circular symmetry of the structures s distinct chiroptical response along their axial orientation can be uncovered via simple spin-coating of the metamolecules on substrates. Our work provides a new strategy to create plasmonic chiral platforms with sophisticated nanoscale architectures for potential applications such as chiral sensing using chemically based assembly systems.
authors.affiliation: Max Planck Institute for Intelligent Systems , D-70569 Stuttgart, Germany.
authors.forename: Maximilian J
authors.initials: MJ
authors.lastname: Urban
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Palash K
authors.initials: PK
authors.lastname: Dutta
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Wang
authors.affiliation: Max Planck Institute for Intelligent Systems , D-70569 Stuttgart, Germany.
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Duan
authors.affiliation: Max Planck Institute for Intelligent Systems , D-70569 Stuttgart, Germany.
authors.forename: Xibo
authors.initials: X
authors.lastname: Shen
authors.affiliation: CAS Key Laboratory of Nanosystems and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China.
authors.forename: Baoquan
authors.initials: B
authors.lastname: Ding
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Ke
authors.affiliation: Max Planck Institute for Intelligent Systems , D-70569 Stuttgart, Germany.|Kirchhoff Institute for Physics, University of Heidelberg , D-69120 Heidelberg, Germany.
authors.forename: Na
authors.initials: N
authors.lastname: Liu
mesh_terms: D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*
chemical_list: D006046:Gold; D004247:DNA