1

1988Carnall, Goodman

Rajnak, Rana

Ln3+

20,000 cm-1

500 nm2.5 eV

2

3

Application: Telecommunications

Kenyon Progr Quantum Electron 26 (2002) 225

Loss spectrum of silica optical fiber in near-IR region

low loss

Er3+ emission in silica host

Er3+ and Sicryst: semiconductor host

injection of e-h pairs

trap

carrier recombin-ation

Auger transfer to free carriers

back-transfer

EDFA

4

Application: Lasers...

http://www.youtube.com/watch?v=CZNFdr4d7g4

http://en.wikipedia.org/wiki/File:YAG2.svg

Nd:YAG

5

Rare earth doped LED with different emitting colors

Application: Phosphors for WLED

WLED

6

VUV: (147,172 nm) to visible (450-610nm)

Application: Phosphors for VUV plasma display

plasma display

PDP

7

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].

LaCl3:Ce3+LaBr3: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

Detector

8

Si

Si2 (e-+h+)

Down-conversion

Downconversion layer

Application: Quantum cutting for Photovoltaics

-Improving the efficiency of conversion of solar

energy into electricity

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

Solar Energy

9

Applications: Sensors

Usually Ln3+ complex emission in solution is not quenched by O2.

Eu(DPIQ)(TTA)3

in MCM41 composites

10 mg/g

20 mg/g

30 mg/g

Eu3+*+O2 → Eu3+ + O2*

Zuo J Solid St Chem 183 (2010) 1715

Sensors

10

Applications: Biomarkers

NH

+HN

H+N

N+H

OH

N

H+NH3C

3Cl-

Hoechst 33258 - NucleusWeakness: UV-Excitation, Broad Emission Range (400-660 nm)

O

SO2NHCH2CH2NH C

O

(H3C)2N

F F

F

F F

(E)

(Z)N

E12353 Endoplasmic Reticulum TrackerWeakness: Expensive 150GBP 2.5g UV-Excitation Staining ER only few minutes

NH

C NH2

N+H2

CH2N

N+H2

2 Cl-

D1306 4',6-diamidino-2-phenylindole, dihydrochloride (DAPI)

DNA and RNA Staining Weakness: UV-Excitation Broad Emission Bands

Commercial Available Markers

O N+(CH3)2Cl-(H3C)2N

CH2Cl

Orange CMTMRos M7510-Mitochrondria Tracker

Weakness: UV-Excitation, Broad Emission Range (550-700 nm)

www.probes.invitrogen.com

Biomarkers

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Theory: Lanthanide ions in crystals

6p

6s5d

4f

5p5s

Empty

Full

E

VB

CB

Example: 4f6

Eu3+ or Sm2+

4f-4f

4f-5dCT

Ionization

Host Ln3+ or Ln2+

“Crystal field”

Trapping electrons, holes or excitons, and modifying vibration

12

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.

eg

ligand π

f

d

f- d π- d

f- f

a2u

t2u

t1u

t2g

π- f

ligand π*

π- π*

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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

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VUV Spectroscopy

Synchrotron

Sample

Excitation MC

Emission MC

MC: Monochromator

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Contents

Electrons, states, energy levels

Allowed Transitions

Forbidden transitions

Nonradiative process

Energy transfer

Some applications