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.tw5.24.2010 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

ww 2eo nn

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Issues with BPM-SHG• Beam walk-off, overlap • Dk (,l,T) narrow

SHG: o+1.3o

Boyd et al., PR137, A1305 (1965)

o

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

ww

wlpnnk

lc

D

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) Type Temperature ( )℃ QPM period (mm)

1260 + 1260 630 (R) SHG 27 11.221064 + 1064 532 (G) SHG 27 6.78

930 + 930 465 (B) SHG 27 4.381260 + 1260 630 (R) SHG 100 11.051064 + 1064 532 (G) SHG 100 6.68

930 + 930 465 (B) SHG 100 4.311990 +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”

OO

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: AFM15

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 MethodPoling 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)

App

lied

Volta

ge (k

V)(1)

0

400

800

1200

1600

Polin

g C

urre

nt (m

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)

18二維非線性光子晶體

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 Conservationwp=ws+wi

Pump

Small Signal

DFG Leftover Pump

Signal

Idler

Amplified SignalResonant Signal

Momentum ConservationKp=Ks+Ki+Kg

20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 160820840860880

900920940960

OPO Curve

Sign

al/F

unda

men

tal W

avel

engt

h (n

m)

Temperature (oC)

Lmm OPO/SHG Tuning Curve Lmm OPO/SHG Tuning Curve Lmm 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

p

p p

D L

D L L

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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

OC AR 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 PPLTL

SDOPO= 7.9mm

LRed-OPO

= 11.6mml

pump = 532nm

lBlue

= 435nml

Red = 630nm

Blue Light Output

SDOPO Max Condition

Out

put P

ower

(mW

)

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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