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1988 Carnall, Goodman Rajnak, Rana Ln 3 + PowerPoint Presentation
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1988 Carnall, Goodman Rajnak, Rana Ln 3 +

1988 Carnall, Goodman Rajnak, Rana Ln 3 +

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1988 Carnall, Goodman Rajnak, Rana Ln 3 +

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  1. 1988 Carnall, Goodman Rajnak, Rana Ln3+ 20,000 cm-1500 nm2.5 eV

  2. Application: Telecommunications EDFA Er3+ emission in silica host low loss Auger transfer to free carriers trap injection of e-h pairs carrier recombin-ation back-transfer Loss spectrum of silica optical fiber in near-IR region Kenyon Progr Quantum Electron 26 (2002) 225 Er3+ and Sicryst: semiconductor host

  3. Application: Lasers... Nd:YAG http://en.wikipedia.org/wiki/File:YAG2.svg http://www.youtube.com/watch?v=CZNFdr4d7g4

  4. Application: Phosphors for WLED Rare earth doped LED with different emitting colors WLED

  5. Application: Phosphors for VUV plasma display PDP VUV: (147,172 nm) to visible (450-610nm)‏ plasma display

  6. Application: Scintillators and dosemeters • γ-ray detection, for medical diagnostic imaging etc • Fast 5d → 4f emission of Ce3+ ( ~ 10-70 ns) • LuI3:Ce3+, with a light yield of 95000 photons per MeV [Krämer] • and for Ce3+ doped into elpasolite hosts such as Cs2LiYBr6 [Bessiere]. Detector LaBr3:Ce3+ LaCl3:Ce3+ Lee IEEE Trans Nucl Sci 52 (2005) 1119 Wojtowicz IEEE Trans Nucl Sci 43 (1996) 2168 Krämer J. Mater. Chem. 16 (2006) 2773 Bessiere IEEE Trans Nucl Sci 51 (2004) 2970 NaI:Tl BGO

  7. Si Si Application: Quantum cutting for Photovoltaics • Improving the efficiency of conversion of solar energy into electricity Solar Energy Downconversion layer Down-conversion 2 (e-+h+) hν > 2Eg (Si) hν’ >= Eg 陈永虎博士2009 nsfc项目和尹民教授的2010 nsfc项目均与此相关

  8. Sensors Applications: Sensors Usually Ln3+ complex emission in solution is not quenched by O2. Eu(DPIQ)(TTA)3 30 mg/g in MCM41 composites 20 mg/g Eu3+*+O2 → Eu3+ + O2* 10 mg/g Zuo J Solid St Chem 183 (2010) 1715

  9. Applications: Biomarkers Biomarkers Commercial Available Markers www.probes.invitrogen.com

  10. Theory: Lanthanide ions in crystals 6p CB Empty 6s 5d Ionization 4f-5d 4f E CT 4f-4f 5p VB Full 5s Example: 4f6 Eu3+ or Sm2+ “Crystal field” Host Ln3+ or Ln2+ Trapping electrons, holes or excitons, and modifying vibration

  11. Theory : Ln3+ in complex (octahedral site, not to scale) • Energies for Multi-electron levels: (crystal-field model and/or ab initio calculations) • Transition Intensities: • Strongly dependent on the ligands surrounding the lanthanide ion.

  12. Experiments • Synthesis • Raman, FTIR, XRD, AFM,EDX etc. • Optical properties: • Light source: Nd3+@YAG + OPA; blackbody radiator lamp; Synchrotron radiation; Ultra short pulse laser • Cryostat (Down to ~2K) • Detectors: PMT or CCD and fast response detectors • Refractive index measurements

  13. VUV Spectroscopy Sample MC: Monochromator Synchrotron Emission MC Excitation MC

  14. Contents Electrons, states, energy levels Allowed Transitions Forbidden transitions Nonradiative process Energy transfer Some applications