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Exciton-plasmom interaction and e nhanced energy transfer in active plasmonic nanosystem. Qu-Quan WANG ( 王取泉 ) qqwang@whu.edu.cn Wuhan University. HK , May, 2010. Our interests:. semiconductor QDs (quantum SWAP, dephasing, spin). Optical nanoemitters (sources). rare-earth NCs
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Exciton-plasmom interaction and enhanced energy transfer in active plasmonic nanosystem Qu-Quan WANG (王取泉) qqwang@whu.edu.cn Wuhan University HK, May, 2010
Our interests: semiconductor QDs (quantum SWAP, dephasing, spin) Optical nanoemitters (sources) rare-earth NCs (dopant-control phase, ET) active plasmonic system antenna spaser Ag nanorod (nonlinear FOM) Metallic nanostructures (plasmons) Au nanowire (avalanche MPL) Ag nanoring (focusing, SP amplification) Au-Ag nanocomplex (plasmon Fano resonances)
Outline Brief introduction 一, 掺杂调控纳光子发射体的光学特性 1.1. Mn掺杂半导体量子点的光学特性 1.2. Ln掺杂调控NaYF4稀土纳米晶的晶相和上转换发射效率 二, 金属纳米结构中表面等离激元Fano干涉效应 2.1. Au-Ag异质纳米棒中双Fano共振效应 2.2.明-暗等离激元能量转移与光调制效应 三, 金属表面等离激元与纳光子发射体相互作用 3.1. Ag纳米颗粒双频天线增强量子点之间非辐射能量转移 3.2. Ag纳米线阵列增强量子点之间辐射能量转移 3.3. Ag纳米环可控增强量子点发射与表面等离激元放大 Summary
* Brief introduction Spaser from two nanosystems: Dye molecule – Au nanoparticle CdS nanorod – Ag thin film
Spaser from Au nanoparticles with dye molecules M. A. Noginov et al., Nature 460, 1110 (2009). The activators are dye nanoemitters
Spaser from Ag thin film with CdS nanowire Rupert F. Oulton et al., doi:10.1038/nature08364 (2009) The activator is CdS nanowire.
一, 掺杂调控纳光子发射体的光学特性 1.1 Mn掺杂半导体量子点的光学特性 1.2 Ln掺杂调控NaYF4稀土纳米晶的晶相和上转换发射效率
磁共振精细结构(EPR) 1.1. Mn掺杂半导体量子点的光学特性ZnSe:Mn/CdSe反核壳量子点中激子极化和存储 ZnSe:Mn/CdSe ZnSe Mn2+ CdSe Exciton |1 Mn2+ |g 共振转移 PL (Exciton) |0
Mn(2+)PL和激子PL发射动力学的差别 Mn(2+)PL和激子PL激发和发射谱的差别
Mn增强 激子PL 强度 Mn延长 激子PL寿命 Appl. Phys. Lett. 96, 123104 (2010)
1.2. Ln掺杂调控NaYF4稀土纳米晶的晶相和上转换发射效率
我们的文章发表在Nano Research 1月份的封面上,优点是生物相容性 2月份Nature上也报道了调控晶相的文章,但没有生物相容性 Nano Res.3, 51 (2010)
二, 金属纳米结构中表面等离激元Fano干涉效应 2.1. Au-Ag异质纳米棒中双Fano共振效应 2.2.明-暗等离激元能量转移与光调制效应
Energy transfer between Au and Ag 692 nm Ag Au 712 nm 786 nm Appl. Phys. Lett. 96, 131113 (2010)
三, 金属表面等离激元与纳光子发射体相互作用 3.1. Ag纳米颗粒双频天线增强量子点之间非辐射能量转移 3.2. Ag纳米线阵列增强量子点之间辐射能量转移 3.3. Ag纳米环可控增强量子点发射与表面等离激元放大
3.1. Plasmon-enhanced nonradiative ET between SQDs by using Ag NPs
Physics process: Plasmon-enhanced FRET ET distance: < 10 nm Donor/acceptors: SQDs in mononlayer film Tool: large Ag NPs Physics effect: Dual-frequency nanoantenna
Dipole and quadrupole SPRs of Ag NPs receiving emitting Size-dependent polarizability of dipole SPRs of Ag NPs:
W/O nanoantenna donor acceptor by single-frequency nanoantenna by dual-frequency nanoantenna
FRET dynamics from donor to acceptor without Ag NPs with Ag NPs
FRET efficiency single frequency dual-frequency antenna Appl. Phys. Lett.96, 043106 (2010)
laser E b PL Ag NR array acceptor SQDs donor SQDs 3.2. Plasmon-mediated radiative energy transfer between semiconductor quantum dots
Physics process: SPP-mediated radiative ET ET distance: ~ 500 nm Donor/acceptors: SQDs / SQDs Tool: Ag NR array Physics effects: subwavelength imaging (near-field SPP coupling, resonant transmission,subwavelength focusing)
Half-wave plasmon resonances in Ag NR arrays Ey - polarized point source Ez - polarized point source L = mSP/2 50 nm 45 nm m = 1 130 nm m = 2 130 nm m = 3 210 nm 220 nm
3.3. Plasmon amplifications in Ag nanoring * Tunable PL enhancement (E) * Plasmon amplifications (T)
D A B E Singly Twinned Crystal (19.5) C Synthesis of singly-twinned Ag nanoring
PL A Laser y in Monolayer SQDs • x Single nanoring CdSe SQDs PL enhanced by a Ag nanoring
a 2m c b 8000 7000 pure SQDs Photon counts (a.u.) 6000 5000 SQDs + nanoring 0 2 4 6 8 t Time delay (ns) d Tunable “hot spots” Time-resolved Photoluminescence H.M.Gong, et al.,Adv.Funct.Mater.19, 298(2009)
Plasmon amplification in Ag nanoring Opt. Express19, 289 (2010)
Summary * Ag nanoparticles enhance nonradiative ET efficiently via dual-frequency antenna effect * Ag nanoring has tunable “hot spot” and could be used in plasmon amplifications * Multiphoton luminescence from the hybrid of SQDs and AgNRs are tunable
Acknowledgement • Profs. Q. K. Xue, J. Zi, J. F. Jia • Profs. Z. Y. Zhang, Q. H. Gong • Drs. X. Y. Shan, Q. Zhang • Drs. L. Zhou, H. M. Gong, S. Xiao X. F. Yu, X. R. Su, Z. K. Zhou