Recent Progress of Photonic Crystals

and Their Device Applications

Recent Progress of Photonic Crystals

and Their Device Applications

Photon, Electron, BandSymposium on the Diversity of Opto-Electronics

In honor of Eli Yablonovitch on his 65th Birthday

SUSUMU NODA

Department of Electronic Science and Engineering,Kyoto University

・ Review of progresses in 3D and 2D photonic crystals

I. Status of 3D Photonic Crystal Research in the early 1990s

II. Developments of 3D Photonic CrystalsIII. Manipulations of Photons by 3D CrystalsIV. Extension to 2D Photonic CrystalsV. Breakthrough in Semiconductor Lasers VI. Thermal Emission Control

・ Summary and Perspective

OutlineOutline

1. The crystals developed at that time had been limited to the "microwave" regime, even though the word of "photonic" was used.

2. It had not been clear what photonic crystals can do exactly and how photonic crystals can manipulate photons.

I．Status of 3D Photonic Crystal Research inthe early 1990s

I．Status of 3D Photonic Crystal Research inthe early 1990s

Issues:1.Developing photonic crystals at optical wavelengths

2. Demonstrating what photonic crystals can do by using the developed crystals step by step.

Alignment and Stacking by Wafer Fusion

(d) Removal of unnecessary substrate

(e) Alignment and stacking.Repetition of (c), (d).

(a) Growth

(b) Formation of Stripes

(b) Wafer fusion

GaAs (or InP)AlGaAs (or InGaAsP)GaAs (or InP)Sub.

Nanometer scale (<50nm) 3D Fabrication

II. Developments of 3D Photonic CrystalsII. Developments of 3D Photonic Crystals

Development of Alignment and Stacking System

Magnified viewof microscope

Overview image

Developed 3D Photonic Crystal

m

10m700nm

S. Noda, et al., Science 289 (28 July 2000) 604K. Ishizaki and S. Noda, Nature 460, 367 (2009)

m

10m

Transmission Reflection

Tran

smitt

ance

Ref

lect

ance

100

10-1

10-2

100

10-1

10-2

Wavelength (nm)1000 1200 1400 1600

=0º=10º=20º

=30º=40º

=0º

0.7m

Inhibition of emission

Strong emission

1. Spontaneous emission control

Ogawa, Noda, Science 305, 227 (2004).Noda, et al, Nature Photonics,3, 129 (2007)

0.7m0.7m

0.7m0.7m

0.7m0.7m

0.7m

F

E

D

C

B

A

G

PC

F

B

PC

C

PC

DPC

GPC

E

PC

wavelength/m1.2 1.4 1.6

10dB

A

PC

III. Manipulations of Photons by 3D CrystalsIII. Manipulations of Photons by 3D Crystals

Freq

uenc

y (c

/a)

0.40

0.35

0.30

0.25

0.20 WavenumberM X1 M X2 M

Band Structure of Infinite Crystal without Surface

Freq

uenc

y (c

/a)

Air l

ight

-line

WavenumberM X1 M X2 M

Air l

ight

-line

0.40

0.35

0.30

0.25

0.20

Surface Modes are generated

-M direction

PC0 |E| Max

a2

Air

X1

X2

yz

x a

Mx

y

Surface

Interesting relevance to the surface plasmon-polaritoneffect of metals and the related surface photon physics

3. Light Control at Surface

Max

0

2 mx

y

K. Ishizaki, S. Noda, et al,Nature 460, 367 (2009).

2D Photonic Crystal0

0.1

0.2

0.3

0.4

FREQ

UEN

CY

[c/a

]

X J2D Bandgap

Calculation and Fabrication Techniques developed for 3D Photonic crystals also induced Rapid Progress in 2D Photonic Crystals.

IV. Extension to 2D Photonic CrystalsIV. Extension to 2D Photonic Crystals

Manipulation of Photons by 2D Photonic Crystals

A. Fundamental of Manipulation of Photons B. Photonic NanodevicesC. Concept to Increase Q FactorD. Dynamic Q Factor Control of Nanocavity

and Stop LightE. Raman Scattering in high-Q NanocavityF. Toward Quantum ApplicationG. Extension to New Materials

f1, f2, fi,…

fi

fi

m

250nm

1500 1550 1600Wavelength (nm)

Inte

nsity

(a.u

.)

=0.4nmQ=3800

a=420nmSi on Insulator

S. Noda, et al, Nature 407(2000) 608.

A. Fundamental Building Block to Manipulate Photons

Trapping and emission of photons

Song, Noda, et al, Science 300, 1537 (2003)

B. Photonic Nanodevices (Heterostructure)

C. Finding of Concept to Increase Q factor of Nanocavity

ShiftQ=3,800

Q>40,000

Akahane, Asano, Song, Noda, Nature (Oct., 2003)

Gentle

Key Point to Increase Q factor of Nanocavity“Gentle Confinement”

0

-10 -5 0 5 10Wave vector []

Four

ier t

rans

form

edel

ectri

c fie

ld [a

.u.]

Leaky region

0

-10 -5 0 5 10Wave vector []

Four

ier t

rans

form

edel

ectri

c fie

ld [a

.u.]

Ele

ctric

fiel

d [a

.u.]

Real space coordinate []

0

-10 0 10

L=2.5

Ele

ctric

fiel

d [a

.u.]

Real space coordinate []

0

-10 0 10

Nanocavity

a=420nm

Gaussian

2D PC Slab

Starting Cavity Structure

Abrupt

Photonic Double Heterostructure

a1 a2 a1

PC-I PC-II PC-I

Mode GapFr

eque

ncy

(c/a

2)

Transmission

Real space

Mode Gap

Freq

uenc

y (c

/a2)

Transmission

Real space

Photon Confinement

a1

PC-I

For Ideal Gaussian Confinement

-5 50Space (a2)

Almost Gaussian-like Confinement

+

-

0

III I

a１=410nm a２=420nm

B.S.Song, S.Noda, et al, Nature Materials (Feb., 2005)Highest Q of 4,300,000 has been achieved

Dynamic Control of Nanocavity Q

I) When we introduce photons into nanocavity,

----- Q should be Small

II) Once the photons are introduced into the nanocavity,

----- Q should be Increased Rapidly

III) When we release photons from nanocavity

----- Q should be decreased rapidly

D. Dynamic Q Factor Control of Nanocavity

Nanocavity

Waveguide

inQ

vino

total Q/Q/Q/ 1]cos1

[11

Perfect Mirror

vQ

(Phase Difference: )Interference

Refractive Index Change

Q can be changed from min (Qin0/2) to max (Qv)by changing from 0 to

Destructive: Leakage to the waveguide is suppressed and Qin increases dramatically

Constructive: Leakage to the waveguide increases and Qin decreases

Tanaka, Noda, et al,CLEO/PR 2005 andNature Materials, 2007

Mechanism of Dynamic Q Control

Stop Light (On-chip Catch & Release Operation of Optical Pulse)

Trap pulseRelease Pulse

F. Extension to New MaterialSuppression of Undesired NonlinearPhenomena (TPA)Si-Based Nanocavity

Serious Two Photon Absorption Problem

SiC

SiC

5 m 1 m

Introduction of Silicon Carbide (SiC)

Inte

nsity

(a.u

.)

Wavelength (nm)

1450 1500 1550 1600

waveguide

1450 1500 1550 1600

cavity

Near-field pattern

Operation in Wideband Frequency Regime

SiC (Electronic Bandgap of 2.2-3.2 eV)

G. Quantum Application (I)

(see also Noda, Science (13 Oct. 2006))

Quantum dots

Nano-lasers and Strong Coupling PhenomenaCaltech: Yoshie, et al, Nature (2004) UCSB: Strauf, et al, Phys.Rev.Lett. (2006)ETH: Hennessy, et al, Nature (2007)Tokyo: Nomura, et al, Optics Exp. (2007)Stanford: Vuckovic, et al, Nature (2007)

(I) High-Q Nanocavity + Quantun Dots

Akahane, Noda, et al, Nature (2003)

(II). Strong Coupling between Nanocavitiesthemselves (and Its Dynamic Control)

Ex: Quantum gate using coupled cavities (Proposal)

M3 34 M656

2 2 2 2

Waveguide 1

22

Target qubit Control qubit

Cavity 3 Cavity 4 Cavity 5 Cavity 6

Waveguide 2

4y 5x

Mx My

xy

22|x› |y›

|g›0 0

|y›-|g›|x›-|g›

QD QD

F. Quantum Application (II)

Cavity A Cavity B

Strong coupling between nanocavities at distant positions

For realizing flexible architecture and on-demand dynamic control without cross talks

Realization of strong coupling between nanocavitiesthrough a waveguidewhile concentrating photons in nanocavities not in the waveguide

Relationship between escape time from nanocavity to waveguide in, and photon propagation time through the waveguide Tp:

in >> Tp

Condition of round trip phase difference between nanocavitiesthrough the waveguide:

= (2m+1)

0 100 200

Eneg

ry (a

.u.)

Time (ps)

Cavity A Cavity B WaveguideCavity A Cavity B

Calculated Results

The Condition

Si

aw 3511 .

w1 w2 w3

aw 3702 . aw 3503 .aw 3

Reflector CCavity A Cavity B

Reflector D

Waveguide

202a=82.8 m17a=7.0 m

a

bc

Preparation of Sample

Multistep Nanocavity

w

Experimental Results (Strong Coupling)

0 100 200 300 400 500Time (ps)

Inte

nsity

(a.

u.)

Cavity ACavity B

Time Domain Measurement

1536 1538 1540 1542

Wavelength (nm)

Inte

nsity

(a.u

.)

3.3 pm 3.3 pm

150 pm

Spectral Regime

1539.3 1539.4 1539.5 1539.6

Wavelength (nm)

Inte

nsity

(a.u

.)

Experimental Results (Dynamic control)

Cavity A Waveguide

Control light

Cavity B

Cavity ACavity B

Inte

nsity

(a.u

.)

0 100 200 300 400

Cavity ACavity B

Time (ps)

Inte

nsity

(a.u

.)

0 100 200 300 400Time (ps)Time (ps)

Inte

nsity

(a.

u.)

First observation of dynamic control of coupled state between high-Q nanocavities

Sato, Noda, et al, Nature Photonics, (Jan. 2012)

A. Perfect Single-Mode Broad-Area Oscillation

B. Generation of Unique Beam Patterns

C. Blue-Violet Surface-Emitting Oscillation

D. High-Efficiency and High-Power Operation

E. Beam Steering Functionality

Broad Area Control of Photons

IV. Breakthrough in Semiconductor LasersIV. Breakthrough in Semiconductor Lasers

Imada, Noda, et al, APL 75 (1999) 316Noda, et al, Science 293 (2001) 1123

Surface emitting region

Active layerLower clad

Photonic crystal

Upper clad

Substrate

Electrode

Electrode

Carrier block

Contact layer

A

B

Device structure and lasing mechanism

-X

-M

A. Perfect Single-Mode Broad-Area Oscillation

Perfect Single

Mode Oscillation

Surface Emission

Inplane Couling

p-AlGaAs Carrier Block

Electrode

Electrodep-GaAs Contact

p-AlGaAs CladPhotonic Crystal

InGaAs Active

n-AlGaAs Clad

Device fabricationInGaAs/GaAs System

Electrode

50x50m2

Side View Top View

Fused Interface

Near-field pattern and lasing spectra

Broad Area Coherent Lasing Oscillation

Surface Emission

Inplane Couling

B. Generation of Unique Beam Patterns

- Max.+ Max. 0

y

x

Phase shift Phase shift

Phase shift

Phas

e sh

ift

Phase shift

Phas

e sh

ift

Beam pattern control

Far-field interference should be changedA range of beam patterns are expected to be generated

287nm

29.2m1°

29.2m

29.2m

Engineering in crystal structure and beam pattern

Miyai, Noda, et al, Nature, 441, 946 (2006).

Two types of doughnut beams

1ºBeam Pattern

:Polarization :Polarization

Tangential Polarization

Radial Polarization

Doughnut beam with radial polarization

Tight Focusing Operation

Tight Focusing by much smaller than

wavelengths is Expected

High NA Lenz.

Component Remains

C. Blue Violet Surface-Emitting Operation

n-AlGaN cladding

n-GaN substrate

2D GaN/Air PCInGaN MQW

p-AlGaN cladding

p-contact

n-contact

InGaN/GaN system

ドーナツ状のビーム

Magnify

1 degree

Far-field pattern

Near- and Far-Field Patterns

Near Field Pattern (Lasing Oscillation)

Before Injection

Top ViewBefore Current Injection

m

Matsubara, Noda, et al, Science 319, 445 (2008).

y

x

D. High-Efficiency and High-Power Operation

Control of unit cell structure

Cancelled-Out Doughnut Beam

z

x

y

x

y

x

y

Cancellation Suppressed

Circular Beam

z

Unit cell structure and efficiency(Operation wavelength: 980nm)

Circle

PEA

K P

OW

ER (m

W)

CURRENT (mA)

(pulse 500ns, 1kHz)Rectangular

triangle

0

50

100

150

200

250

0 100 200 300 400 500

triangle

Upside-Down Configuration and Introduction of Interference Effects between Downward and Upward Emitting Light

P-clad

N-cladActive

Emitting region

N-electrode

P-electrode

ReflectanceReflector

d

Optimization of device configurationand introduction of interface effect

E. Beam-Steering Functionality

· Important for wide range of laser applications

・・・

· Achieved using complicated optical systems

[1] J. Montagu, Handbook of Optical and Laser Scanning, pp. 417-476, Marcel Dekker (2004).[2] G. Stutz, Handbook of Optical and Laser Scanning, pp. 265-297, Marcel Dekker (2004).[3] A. D. Yalcinkaya, et al.,, IEEE J. Microelectromechanical systems 15, 786-794 (2006).

[1]

[2]

[3]

Galvanometer Polygon mirror MEMS mirror Limit・ Speed・ Size ・ Lifetime

Square lattice photonic crystal

Air hole

a

a

Rectangular lattice photonic crystal

Air hole

a

a’

Composite photonic crystal

Air hole

a a

a' a'a

Composite photonic crystal

-X1

-X2 -M

-X1

-X2 -M

-X1

-X2 -M

~1000 m~300 m

-X1

-X2

Continuous change

Device structure and Fabrication

Compositephotonic crystal

n-Electrode

a: Fixeda’: Continuously changed (Spatially changed)

Active layer

Periods

Position

426 nm

294 nm

a′

a

k

0.15

0

Experimental Results+30°-30°

Angle, (deg)

Kurosaka, Noda, et al, Nature Photonics (July 2010)

Summary and Future ProspectsSummary and Future Prospects

Various new concepts and technologies have been built up in the field of photonic crystals

Now is the time to take on new challenges to achieve ultimate light control based on photonic crystals, in order to realize novel communication and information processing technologies based on the quantum nature of photons, and to develop ultimate broad area coherent lasers, ultrahigh efficient light-emitting devices, sensors, displays, etc.