1. HK, May, 2010 Exciton-plasmom interaction and enhanced energy transfer in active plasmonic nanosystem Qu-Quan WANG ( 王取泉 ) qqwang@whu.edu.cn Wuhan University

2. active plasmonic system semiconductor QDs (quantum SWAP, dephasing, spin) spaser rare-earth NCs (dopant-control phase, ET) antenna Ag nanorod (nonlinear FOM) Au nanowire (avalanche MPL) Ag nanoring (focusing, SP amplification) Optical nanoemitters (sources) Metallic nanostructures (plasmons) Au-Ag nanocomplex (plasmon Fano resonances) Our interests:

3. Outline Brief introduction 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 NaYF 4 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 Summary

4. * Brief introduction * Brief introduction Spaser from two nanosystems: Dye molecule – Au nanoparticle CdS nanorod – Ag thin film

5. M. A. Noginov et al., Nature 460, 1110 (2009). Spaser from Au nanoparticles with dye molecules The activators are dye nanoemitters

6. Rupert F. Oulton et al., doi:10.1038/nature08364 (2009) Spaser from Ag thin film with CdS nanowire The activator is CdS nanowire.

7. 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

8. 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 磁共振精细结构 （ EPR ） Mn 2+ PL (Exciton) Exciton |0  |g|g |1  CdSe Mn 2+ ZnSe ZnSe:Mn/CdSe 共振转移

9. Mn(2+) PL 和激子 PL 激发和发射谱的差别 Mn(2+) PL 和激子 PL 发射动力学的差别

10. Mn 延长 激子 PL 寿命 Mn 增强 Mn 增强 激子 PL 激子 PL 强度 强度 Appl. Phys. Lett. 96, 123104 (2010)

11. 1.2. Ln 掺杂调控 NaYF 4 稀土纳米晶的晶相 和上转换发射效率

14. Nano Res. 3, 51 (2010) 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

15. 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

16. 2.1 Au-Ag 异质纳米棒中双 Fano 共振效应

18. Energy transfer between Au and Ag 692 nm 712 nm 786 nm Au Ag Appl. Phys. Lett. 96, 131113 (2010)

19. 2.2 明 - 暗等离激元能量转移与光调制效应

22. Appl. Phys. Lett. 96, 043113 (2010)

23. 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

24. 3.1. Plasmon-enhanced nonradiative ET between SQDs by using Ag NPs between SQDs by using Ag NPs

25. Physics process: Plasmon-enhanced FRET ET distance: < 10 nm Donor/acceptors: SQDs in mononlayer film Tool: large Ag NPs Physics effect: Dual-frequency nanoantenna

26. Dipole and quadrupole SPRs of Ag NPs Size-dependent polarizability of dipole SPRs of Ag NPs: receiving emitting

27. by single-frequency nanoantenna by dual-frequency nanoantenna W/O nanoantenna donor acceptor

28. without Ag NPs FRET dynamics from donor to acceptor with Ag NPs

30. Appl. Phys. Lett. 96, 043106 (2010) FRET efficiency single frequency dual-frequency antenna

31. 3.2. Plasmon-mediated radiative energy transfer between semiconductor quantum dots acceptor SQDs PL bb laser donor SQDs E Ag NR array

32. 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)

33. 50 nm 130 nm 220 nm 45 nm 130 nm 210 nm Half-wave plasmon resonances in Ag NR arrays E z - polarized point source E y - polarized point source m = 1 m = 3 m = 2 L = m SP /2

34. 3.3. Plasmon amplifications in Ag nanoring * Tunable PL enhancement (E) * Tunable PL enhancement (E) * Plasmon amplifications (T) * Plasmon amplifications (T)

35. C E Singly Twinned Crystal (19.5  ) D BA Synthesis of singly-twinned Ag nanoring

36. CdSe SQDs PL enhanced by a Ag nanoring A x PLPL Laser  in y Single nanoring Monolayer SQDs

37. H.M.Gong, et al., Adv.Funct.Mater.19, 298(2009) a 2m2m c b Tunable “hot spots” Time-resolved Photoluminescence

38. Plasmon amplification in Ag nanoring Opt. Express 19, 289 (2010)

39. 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

40. 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

41. Thank you!