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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.