ferroelectric nanostructures for white laser and high speed electronics applications...
TRANSCRIPT
Ferroelectric nanostructures for white laser and high speed
electronics applications
鐵電相微奈結構與其在雷射與高速晶體管之應用
彭隆瀚台灣大學光電所與電機系[email protected]
5.24.2010 東華大學物理系
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• 鐵電相微奈結構之製備與應用 - 雷射光能轉換 - 次世代電子技術替代方案
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光源與色域
• RGB 雷射之色域顯示,優於習知光源技術
• (630, 532, 465)nm 為 RGB 雷射顯示之優選波長,白光雷射之功率比 2 : 1.4 : 1
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LED vs Laser 投影品質比較• Microvision PicoP• 10 Lumens /WVGA
資料來源 奧圖碼
資料來源 Microvision
• Optoma pk-102• 10 Lumens/HVGA• NT$14,000/set
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雷射在高畫質電視應用
CES 2008 (65”, 73”)• 500 nits• 電力消耗 < 200W
資料來源 三菱電機 雷射電視
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資料來源 三洋電機 雷射投影電視
04. 2009. (100”)• 7000 lm
產業趨勢 : Projector Phone
* US: Logic Wireless “Bolt” 01.2009. 技術 : 深圳 ChinaKing LCoS/LED
* Korea: Samsung “Show-W7900” 01.2009. 技術 : TI-DLP/LED
• US: Microvision “PicoP” 10.2008. 技術 : MEMS/Laser 亞洲光學組裝
• US: 3M“MPro110”LCoS/LED 08.2008.
4.2009. IEEE Spectrum http://www.spectrum. ieee.org/video?id=921
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習知雷射投影之光源技術
資料來源 松下電器 640/532/445nm
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資料來源 Microvision
Wavelength Conversion• Conservation of energy and momentum • Birefringent Phase Matching BPM• 缺點 : 作用光極化 ( 偏振 ) 方向相互垂直
轉換效率較低 (beam walk off)Textbook Example: SHG in KTP (green laser)
w + w = 2w
2'
11 kkk
2eo nn
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Issues with BPM-SHG
• Beam walk-off, overlap • Dk (q,l,T) narrow
SHG: qo+1.3o
Boyd et al., PR137, A1305 (1965)
qo
Giordmaine, PRL 8, 19 (1962) )]/[tan(tan 221eo nn
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雷射光能轉換 相位匹配• 哈佛大學教授 Bloembergen
PR 127, p.1918 (1962) (1981 年諾貝爾物理獎 )
2kw + G = k2w G = 2p/L
週期性結構提供晶格動量 G( 倒戈矢 ) 滿足波長轉換動量守
恆
nnk
lc
2
14 lc : coherent length 同調長度
Ew E2w
lc
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適用於無中心對稱之有機、無機塊材與奈米結構
Design of QPM period
Wavelength (nm) TypeTemperature
( )℃QPM period
(mm)
1260 + 1260 630 (R) SHG 27 11.22
1064 + 1064 532 (G) SHG 27 6.78
930 + 930 465 (B) SHG 27 4.38
1260 + 1260 630 (R) SHG 100 11.05
1064 + 1064 532 (G) SHG 100 6.68
930 + 930 465 (B) SHG 100 4.31
1990 +1990 995 SHG 27 29.5
1064 1550 +3393 DFG 174 29.5
Period, Λ
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Nonlinear Photonic Crystal
Engineered structures with spatial contrast in c(1) or c(2) to control the propagation of light in the material
c(1) PC : modification of wave dispersion photonic bandgap and linear optics, dmin~ l/n
c(2) quadratic PC: wavelength conversionsoliton,quantum entanglement …dmin~l/dn
LEOS New LettersAug, 2003
Physics TodayMay, 1994
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Example of Ferroelectric Switching
Ec~ 21.5KV/mm
Li+ ion
Haycock et al, APL 48, 698 (1986)
利用電壓 (>15kV) 形成疇反轉與週期控制
“poling”
O
O
OLi
Nb
* E-field activated domain reversal on LiNbO3
* Eapp> Ec: coercive field* Nonlinear Photonic Crystal
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Submicron-Domain Research• LiNbO3, LiTaO3 (congruent, stoichiometric, doped)• Scanning Force Microscopy (SFM) to write/read• NIMS, Tohoku U./Pioneer (Japan)
NCST, ORNL (USA); Tel Aviv U. (Israel)
APL 85, 452 (2004), CG-LN, Tel Aviv U.
Mat. Sci. Eng. B120, 130 (2005), Pioneer/Tohoku MgO:LN
Area density ~1.5TBit/inch2
on CG-LT
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V
SFM tip
Bias voltage
Metal substrate
PsLiNbO3
LiNbO3
5 mm
180°-domain parallel to c-axis
Conductive tip with 20 nm curvature
Polarization inverted by applying a bias voltage
Domain inverted by tip scanning on surface
Strategy for sub-mm domain: AFM
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The Kinetics of Domain Inversion
(d) Rapid Coalescence
Ps
+Z
[1] G. D. Miller, Ph.D. dissertation, Stanford University, 1998
Model : Nucleation Control Sidewise Wall Model [1]:
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High Voltage Poling Method
Poling waveform model : Nucleation Control Sidewise Wall Model
0 500 1000 15000
4
8
12
16
20
Applied Voltage Poling Current
(6)
(5)
(4)
(3)
(2)
Time (ms)
Ap
pli
ed V
olt
age
(kV
)
(1)
0
400
800
1200
1600
Po
lin
g C
urr
ent
(A
)
Stanford U. J. Opt. Soc. Am. B, 12, 2102 (1995)
Nucleation
Tip / Wall Propagation
StabilizationStabilization
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(b)
(a)
(d)
(c) (a)
(b)
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二維非線性光子晶體
+ w w→2w
二次諧波產生
Optics Measurement
KωKω K10
G1,0
G1,0
λp=929.5nm
G1,-1 G1,1
λp=923.5nm
G1,-2 G1,2
λp=908.2nm
K11
G1,1
G1,-1
K12
G1,-2
G1,2
Two-dimensional PPLT
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OPTICAL PARAMETRIC OSCILLATION
Energy Conservation p= s+ i
Pump
Small Signal
DFG Leftover Pump
Signal
Idler
Amplified Signal
Resonant Signal
Momentum ConservationKp=Ks+Ki+Kg
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光學參量振盪 : 無中生有
光學參量放大‥
電晶體
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綠 - 紅藍雷射光能轉換技術
L=10mm PPLT Self-doubling OPOBlue Laser
L=15mm PPLT OPO Red Laser
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光學參量上下轉換
LOPO=2LSHG
DESIGN OF SELF-DOUBLING OPO
40 60 80 100 120 140 160820
840
860
880
900
920
940
960
OPO Curve
Sig
nal
/Fu
nd
amen
tal W
avel
eng
th (
nm
)
Temperature (oC)
m OPO/SHG Tuning Curve m OPO/SHG Tuning Curve m OPO/SHG Tuning Curve
SHG Curve
1st order QPM-OPO generating 2nd order QPM-SHG Blue Laser
TPM LOPO LSHG lsignal lSHG
163.3℃ 7.90mm 3.95mm 869.1nm 434.6nm
1 1
2 2
2=0
2 2=0
2
OPO p s iOPO
SHG b s sOPO SHG
k k k k G G
k k k k G G
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Effective Nonlinear Coefficient is less for 2nd QPM-SHG!!
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EXPERIMENT SET-UP
OvenR.O.C5 cm
R.O.C5 cm
532nmPump Laser
4KHz 17.2nsFilter
Blue Light
OC IC
Cavity Mirror Specification
ICAR 532nm @0° IncidenceHR 868nm @0° IncidenceHR 434nm @0° Incidence
OCAR 532nm @0° IncidenceHR 868nm @0° Incidence
Material CLT
Size 15mm × 6mm ×0.5mm
Grating period 7.90mm
Temperature 143.3℃
Pump wavelength 532nm
SHG wavelength 434.6nm
Antireflection coating
No
℃
Power Meter
28mm Cavity
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進行中之研究
0 100 200 300 400 5000
5
10
15
20
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3010mm SDOPO + 15mm Red OPO PPLT
SDOPO= 7.9m
Red-OPO
= 11.6m
pump
= 532nm
Blue
= 435nm
Red
= 630nm
Blue Light Output
SDOPO Max Condition
Out
put P
ower
(m
W)
Average Input Power (mW)
Red Light Power
b~13.3%
r~10.5%
Self-Doubling OPO cascading Red OPOWhite Light Laser
Self-Doubling OPO cascading Red OPOWhite Light Laser Self-doubling Blue OPO
Red OPO
L=20mm, 100mW- White Light Laser Head
•白光雷射技術 ( 應用 )•阿秒雷射波合成 ( 基礎 )
100mW PPLT 白光雷射晶片
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Multi-harmonics generation
20% conversion efficiency
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