title: Heat-enhanced symmetry breaking in dynamic gold nanorod oligomers: the importance of interface control.
abstract: We reported a surprisingly strong plasmonic circular dichroism (PCD) response in side-by-side (SS) oligomers of gold nanorods (GNRs) just by a simple heat treatment. The maximal anisotropic (g) factor achieved was up to 0.065, one of the largest reported for plasmon-enhanced chiral nanostructures based on a bottom-up strategy. The introduction of chiral thiolated molecules is suggested to guide the symmetry breaking of GNR assemblies and heat treatment provides the necessary energy to assist this process, and thus produces a huge PCD. Furthermore, we first demonstrated the critical role of the non-chiral component (surfactant layer) on the gold nanorod surface in mediating symmetry breaking. Our findings highlight the importance of interface control in the formation of chiral configuration for a plasmonic nanoparticle system. It offers new possibilities for fabricating nanostructures with strong chiroptical activity by the rational design of interface layers.
authors.affiliation: Department CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China. wuxc@nanoctr.cn.
authors.forename: Jiao
authors.initials: J
authors.lastname: Yan
authors.forename: Shuai
authors.initials: S
authors.lastname: Hou
authors.forename: Yinglu
authors.initials: Y
authors.lastname: Ji
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Wu