title: Released plasmonic electric field of ultrathin tetrahedral-amorphous-carbon films coated Ag nanoparticles for SERS.
abstract: We have demonstrated the plasmonic characteristics of an ultrathin tetrahedral amorphous carbon (ta-C) film coated with Ag nanoparticles. The simulation result shows that, under resonant and non-resonant excitations, the strongest plasmonic electric field of 1 nm ta-C coated Ag nanoparticle is not trapped within the ta-C layer but is released to its outside surface, while leaving the weaker electric field inside ta-C layer. Moreover, this outside plasmonic field shows higher intensity than that of uncoated Ag nanoparticle, which is closely dependent on the excitation wavelength and size of Ag particles. These observations are supported by the SERS measurements. We expect that the ability for ultrathin ta-C coated Ag nanoparticles as the SERS substrates to detect low concentrations of target biomolecules opens the door to the applications where it can be used as a detection tool for integrated, on-chip devices.
authors.affiliation: 1] National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, PR China [2] Department of Applied Physics, Zhejiang University of Technology, Xiaoheshan, Hangzhou 310023, PR China.
authors.forename: Fanxin
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Applied Physics, Zhejiang University of Technology, Xiaoheshan, Hangzhou 310023, PR China.
authors.forename: Chaojun
authors.initials: C
authors.lastname: Tang
authors.affiliation: National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhan
authors.affiliation: National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, PR China.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Chen
authors.affiliation: SAE Magnetics (HK) Ltd (TDK), Dongguan 523087, PR China.
authors.forename: Hongtao
authors.initials: H
authors.lastname: Ma
authors.affiliation: National Laboratory of Solid State Microstructures and School of Physics, Nanjing University, Nanjing 210093, PR China.
authors.forename: Zhenlin
authors.initials: Z
authors.lastname: Wang