Kato Group, Nanoscale Quantum Photonics...
Transcript of Kato Group, Nanoscale Quantum Photonics...
開拓研究本部 加藤ナノ量子フォトニクス研究室理化学研究所
Quantum Optoelectronics Research Team, RIKEN Center for Advanced Photonics
カーボンナノチューブ・オプトエレクトロニクスCarbon nanotube optoelectronics
カーボンナノチューブの光物性Optical properties of carbon nanotubes
カーボンナノチューブ・フォトニクスCarbon nanotube photonics
1100 1200 1300 1400 15000
50
100
150
PL
inte
nsity
(ar
b. u
nits
)
Emission wavelength (nm)
with SWCNTs without SWCNTs
フォトニック結晶共振器による発光増強Emission enhancement by photonic crystal cavities
Appl. Phys. Lett. 101, 141124 (2012).
PL (counts/s)0 10050
2 µm
1395 nm
2 µm
1μm
λex = 857 nm(resonant)WGM
PL (counts/s)0 100 15050
2 µm
λex = 857 nm(resonant)CNT
PL (counts/s)0 100 200
2 µm
1420 1430 1440Emission wavelength (nm)
40
0
80
Pho
tolu
min
esce
nce
(cou
nts/
s)
Data
WGM peakCNT peak
微小ディスク共振器との光結合Optical coupling to microdisk resonators
Appl. Phys. Lett. 102, 161102 (2013).
Catalyst
CNT
Nanobeam
2 μm
CNT
PL
inte
nsity
(nm
)
Emission wavelength(nm)
dataCNTCavity
10
0
20
30
0
500
1000
1500
1360 1380 1400
P = 120 μWλex = 799 nm
Fit
dataFit
ナノビーム共振器との高効率結合Efficient coupling to nanobeam cavities
Nat. Commun. 5, 5580 (2014).
0
I PL
(a.u
)
500 1000 1500 2000time (μs)
0
24
6
Vg
Vb
Va
Contact to gate
Contact to CNT
Catalyst
Local gate
CNT
ゲート電圧による光パルス列生成Gate‐voltage generated optical pulse trains
Nat. Commun. 6, 6335 (2015).
θ
x
y
z
CNTSi substrate
Objectivelens
PL
1100 1200 1300 1400
0
1
2
3
4
PL
inte
nsity
(ar
b. u
nits
)
Emission wavelength (nm)
RCP LCP
ex = 780 nmP = 26 mW
(9,7)CNT
Si
-180 -90 0 90 180
-0.6-0.30.00.30.6
12801300
12801300
0.0
0.3
0.6
0.9
0 1 2
I R
CP, I
LC
P
(arb
. uni
ts)
Em
issi
on
wa
vele
ngth
(nm
)
LCP
RCP
RCPLCP
Angle of incidence (degrees)
PL intensity (arb. units)
外因性キラリティによる巨大円二色性Giant circular dichroism induced by extrinsic chirality
Phys. Rev. X 4, 011005 (2014).
10
1
0.8 0.9 1.0 1.1 1.2-2
-1
0
1
2
Ga
te V
olta
ge (
V)
Emission Energy (eV)
(10,6)
PL In
tensity (arb
. units)
発光のゲート制御Gate control of photoluminescence
Phys. Rev. B 84, 121409(R) (2011).
0.0 0.5 1.0 1.5 2.0 2.50
200
400
600
800
PL
inte
nsi
ty (
arb
. un
its)
Nanotube length (m)
L = 610 nm
励起子拡散長の計測Exciton diffusion length
Phys. Rev. Lett. 104, 247402 (2010).
PL excitation spectroscopy
Emission energy (eV)0.8 0.9 1.11.0
1.55
1.60
1.65
1.70
Exc
itatio
n en
ergy
(eV
)
1.2
Em
issi
on in
tens
ity (
a.u.
)
0
5
10
15
20
1100 1200 1300 1400 15000
1000
2000
3000
4000
5000
cou
nts/
sec
emission wavelength (nm)
Nanotube
2 µm1 µm
SEM image Si
2 µm
PL images
共焦点顕微分光システムによる単一ナノチューブの光学測定Optical characterization of individual carbon nanotubes
炭素源
CNTの合成
PressureGauge
PressureGauge
PressureGauge
MFC
MFCMFC: Mass Flow Controller
圧力調整
炭素源
バブリング用アルゴン
触媒金属の還元
化学気相成長装置Chemical vapor deposition
Reflectivity (arb. u
nits)5
3
1
PC (nA)2
1
励起子解離の光電流検出Photocurrent detection of exciton dissociation
Phys. Rev. Lett. 112, 117401 (2014).
PL (arb. u
nits)
8
6
4
0
21μm
a2
a1
C=na1+ma2
グラフェンシートが筒状に巻かれているものGraphene sheet rolled up seamlessly
カイラリティ (n,m) で構造が一意に決まるChirality (n,m) completely determines the structure
直径はナノ、長さはミクロンDimeter of ~1 nm, length > microns
単層カーボンナノチューブSingle‐walled carbon nanotubes
光量子工学研究センター 量子オプトエレクトロニクス研究チーム
励起子ー励起子消滅における一次元効果Exciton‐exciton annihilation
Phys. Rev. B 91, 125427 (2015).
• Simulations
Generation rate 𝑔 𝜏
Intrinsic decay rate Γ𝜏
10‐1 100 101 102 103 104
101
100
10‐1
10‐2
10‐3
10‐2 105
102
Linear𝑃𝐿 ∝ 𝑃
Sublinear
𝑃𝐿 ∝ 𝑃
◦ Measurements
10‐2
Excitation power 𝑃 (μW)
PL intensity
(arb. u
nits)
10‐1 100 101 102
105
104
103
102
101104 105103
106(8,7)𝐿 = 1.17 μm
Nanoscale Quantum Photonics Laboratory, RIKEN
ゲート電圧によるトリオン生成Gate‐voltage induced trionsPhys. Rev. B 93, 041402(R) (2016).
0.8 0.9 1.0-2
-1
0
1
2
Gat
e vo
ltag
e (V
)
Emission energy (eV)
101
102
103
104
PL
(cou
nts
s-1)
T+
T-
KX
−−+
++−
http://katogroup.riken.jp/
冷たい励起子の電界発光Cold exciton electroluminescence
Appl. Phys. Lett. 110, 191101 (2017).
BiasVDSGate1
VG1 Gate2VG2
0
5
10
15
EL
(co
unt
s/s)
1200 1300 1400 1500
0
500
1000
PL
(co
unts
/s)
Wavelength (nm)
EL
PL P = 5 Wλex = 836 nmVG1=VG2= 0 VVDS= 0 V
VG1 = +16 VVG2 = −16 VVDS = 5 V
光双安定性と光メモリOptical bistability and optical memory
ACS Photonics 5, 559 (2018).
Set
BiasReset
Adsorbed molecules
Nanotube
P
t
1.00
1.05
500 700 9001.00
1.05
0
Excitation power (μW)
Normalized PL1
Em
issi
on
ener
gy (
eV)
室温における単一光子発生Room‐temperature single
photon emissionPhys. Rev. Applied 8, 054039 (2017).
‐80Time (ns)
‐60 ‐40 ‐20 806040200
Count rate (h
our‐1)
0
30
20
10
フォトニック結晶共振器における双共鳴Double resonance in photonic crystal nanocavities
Phys. Rev. Applied 3, 014006 (2015).
Emission wavelength (nm)1000 1100 12001050 1150
Exc
itatio
n w
ave
leng
th (n
m)
900
800
700
750
850
a = 270 nm, L2
a = 290 nm, L1
a = 380 nm, L3
a = 300 nm, L5
PL (arb. units)1.00.0 0.5
暗い励起子準位の電界活性化Electrical activation of dark
excitonic statesNano Lett. 16, 2278 (2016).
300
200
0
100
Pho
tocu
rren
t (p
A)
Excitation energy (eV)1.3 1.4 1.5 1.6 1.7
0
5.0
7.5
2.5
Ele
ctric
fiel
d (V
/μm
)
n-m が3で割り切れなければ直接バンドギャップDirect band gap if n-m ≢ 0 (mod 3)
分光により (n,m) の同定が可能Spectroscopic determination of (n,m) possible
Laser heating
シュタルク効果Spectral tuning by Stark effectAppl. Phys. Lett. 105, 161104 (2014).
PL (arb. units)1050
0.91 0.92 0.93 0.94Emission energy (eV)
Electric field (V/m)
0
15
10
5
ナノビーム共振器との光結合制御Spectral tuning of optical coupling
Appl. Phys. Lett. 112, 021101 (2018).
DOC (6,5)MeO‐Dz
SiSiO2
Si
SiO2
シリコン微小共振器による単一光子発生レート増強
Enhanced single photon emission using silicon microcavitiesPhys. Rev. Applied 8, 054039 (2017).
0.8 0.9 1.0 1.1100
101
102
103
PL in
tens
ity (
a.u.
)
Emission energy (eV)
Vg=−1.5 V𝑇
𝐸
励起子ーキャリア相互作用に対する分子遮蔽効果
Molecular screening effects on exciton‐carrier interactionsAppl. Phys. Lett. 113, 121105 (2018).
有機分子による多体効果制御Organic molecular effects on
many‐body interactionsJ. Phys. Chem. C 123, 5776 (2019).
Exc
itatio
n en
ergy
(eV
)
0.8 0.9 1.0 1.1
1.4
1.5
1.6
1.7
1.4
1.5
1.6
1.7
5000
10000
PL (counts/s)
PL (counts/s)
0
250
500
0
Emission energy (eV)