title: Tailoring Plasmonic Enhanced Upconversion in Single NaYF4:Yb(3+)/Er(3+) Nanocrystals.
abstract: By using silver nanoplatelets with a widely tunable localized surface plasmon resonance (LSPR), and their corresponding local field enhancement, here we show large manipulation of plasmonic enhanced upconversion in NaYF4:Yb(3+)/Er(3+) nanocrystals at the single particle level. In particular, we show that when the plasmonic resonance of silver nanolplatelets is tuned to 656 nm, matching the emission wavelength, an upconversion enhancement factor ~5 is obtained. However, when the plasmonic resonance is tuned to 980 nm, matching the nanocrystal absorption wavelength, we achieve an enhancement factor of ~22 folds. The precise geometric arrangement between fluorescent nanoparticles and silver nanoplatelets allows us to make, for the first time, a comparative analysis between experimental results and numerical simulations, yielding a quantitative agreement at the single particle level. Such a comparison lays the foundations for a rational design of hybrid metal-fluorescent nanocrystals to harness the upconversion enhancement for biosensing and light harvesting applications.
authors.affiliation: 1] Department of Physics, The University of Texas at Austin, Austin, TX 78712, USA [2] Department of Physics, Wuhan University, Wuhan 430072, P. R. China.
authors.forename: Ya-Lan
authors.initials: YL
authors.lastname: Wang
authors.affiliation: Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Nasim
authors.initials: N
authors.lastname: Mohammadi Estakhri
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Amber
authors.initials: A
authors.lastname: Johnson
authors.affiliation: Department of Physics, Wuhan University, Wuhan 430072, P. R. China.
authors.forename: Hai-Yang
authors.initials: HY
authors.lastname: Li
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Li-Xiang
authors.initials: LX
authors.lastname: Xu
authors.affiliation: 1] Department of Physics, The University of Texas at Austin, Austin, TX 78712, USA [2] ICQD/HFNL, University of Science and Technology of China, Hefei 230026, P. R. China.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Alù
authors.affiliation: Department of Physics, Wuhan University, Wuhan 430072, P. R. China.
authors.forename: Qu-Quan
authors.initials: QQ
authors.lastname: Wang
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Chih-Kang Ken
authors.initials: CK
authors.lastname: Shih