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peng@cc.ee.ntu.edu.tw

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

25

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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