Nanophotonics

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Nanophotonics Class 5 Rare earth and quantum
dot emitters
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Optical doping with lanthanide ions
H He Li Be B
C N O F Ne Na Mg Al Si P S Cl Ar K Ca S
c Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb S
r Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs
Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
Fr Ra Ac Rf Db Sg Bh Hs Mt Uun Uuu Uub Ce Pr
Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Th Pa U N
p Pu Am Cm Bk Cf Es Fm Md No Lr

La3 Xe 4f n n1-14 .4f n 5s2 5p6
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Energy levels of lanthanide ions
Egap(Si)
1.5 µm
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Ce Pr Nd Pm Sm Eu Gd Tb Dy
Ho Er Tm Yb Lu
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Europium protects the euro
J.F. Suyver, A. Meijerink (UU)
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Lanthanide bar codes
Dejneka, PNAS 100, (2003)
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Optical doping with lanthanide ions
H He Li Be B
C N O F Ne Na Mg Al Si P S Cl Ar K Ca S
c Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb S
r Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs
Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
Fr Ra Ac Rf Db Sg Bh Hs Mt Uun Uuu Uub Ce Pr
Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Th Pa U N
p Pu Am Cm Bk Cf Es Fm Md No Lr

La3 Xe 4f n n1-14 .4f n 5s2 5p6
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Chemistry (outer-shell behavior) is similar
Erbium
Prasaeodymium
A. Polman et al., Appl. Phys. Lett. 62, 507
(1993), J.S. Custer et al., J. Appl. Phys. 75,
2809 (1994)  
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Silica optical fiber transmission spectrum
1012 Hz
1.3 ?m
1.55 ?m
wavelength vs. time division multiplexing WDM
Miya et al., Electron. Lett. 15, 108 (1979)
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Erbium transition at 1.5 ?m
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Er absorption and emission cross sections
absorption
emission
G.N. van den Hoven et al. Appl. Opt. 36, 3338
(1997)  
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Erbium photoluminescence in various silicate
glasses
WtotWradCEr-Er?Er?OH
A. Polman, J. Appl. Phys. 82, 1 (1997)
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Local structure around Er in silicate glasses
EXAFS
M.A. Marcus et al., J. of Non-Cryst. Solids 136,
260 (1991)
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Planar optical waveguide
high index
low index
Si

• Waveguide core materials
• silica glass
• Al2O3, Si3N4, .
• polymer
• silicon

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Photonic integrated circuits on silicon
SiO2/Al2O3/SiO2/Si
1 mm
Al2O3 technology by M.K. Smit et al., TUD
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The worlds smallest erbium-doped optical
amplifier
1.53 ?m signal, 1.48 ?m pump, 10 mW, gain 2.3 dB
Waveguide spiral size 1 mm2 minimum bending
radius gt 50 ?m
Appl. Phys. Lett. 68, 1886 (1996)
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From a FOM prototype to a 40 M company
Symmorphix Sunnyvale CA, USA
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1.5 µm microcavity mode imaged through green
upconversion
2 MeV Er implantation, 0.35 at., 800 C anneal
T.J. Kippenberg et al.
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Quantum dot emitters
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Silicon is an inefficient light emitter

• Indirect bandstructure

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SiEr light-emitting diode
Er, O doped c-Si
G. Franzó et al., Appl. Phys. Lett. 64, 2235
(1994), B. Zheng et al., Appl. Phys. Lett. 64,
2842 (1994)
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Silicon quantum dots particles in a box

• 5 ?m SiO2
• 165 keV Si, 1.7?1017 cm-2
• anneal 1100 ?C
• ? nanocrystals 3-5 nm ?

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X-ray Photo-electron spectroscopy
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Luminescence spectrum depends on Si concentration
red-shift for larger nanocrystal size
50 keV Si, 1100 oC/10 min, 500 eV D, 3?1015
cm-2
Bulk Si bandgap 1100 nm
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Shrinking Si quantum dots by oxidation blue shift
?E 300-400 meV
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Compound semiconductor quantum dots PbS
PbS rock-salt structure
5 nm
Nearly spherical shape, crystal facets
Modified slide from D. Vanmaekelbergh
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Compound semiconductor quantum dots CdSe
CdSe wurtzite
Modified slide from D. Vanmaekelbergh
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Luminescence from compound semiconductor quantum
dots
Modified slide from D. Vanmaekelbergh