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PERFOS : R&D platform of Photonics Bretagne
DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
RECENT ADVANCES IN VERY HIGHLY NONLINEAR CHALCOGENIDE PHOTONIC
CRYSTAL FIBERS AND THEIR APPLICATIONS
David Méchin1, Laurent Brilland1, Johann Troles2,3, Thierry
Chartier2,4, Pascal Besnard2,4, Guillaume Canat5, Gilles Renversez6
1PERFOS (France), 2UEB (France), 3EVC (France), 4FOTON (France), 5ONERA (France), 6Institut Fresnel (France).
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Introduction
Chalcogenide Microstructured Fibers (EVC, PERFOS)
Four-wave Mixing Based Wavelength Conversion (FOTON)
Mid-IR Supercontinuum And Fourth-order Cascaded Raman Shift (ONERA)
Brillouin Fiber Laser (FOTON)
Conclusion and Perspectives
Outline
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Introduction
Last month, the Perfos association became « Photonics Bretagne », the official
photonics cluster of the Bretagne region in France.
Perfos is now the R&D platform of the
cluster and continues to design and
fabricate specialty microstructured fibers,
both in silica and chalcogenide.
3
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Introduction
Evosens
MicroModule
CNRS LSOL
RESO
PERDYN
Amgmicrowave, FCequipments, Ideoptics, Idil, Ixfiber, Jmdthèque, Keopsys, Kerdry, Laseo, Laserconseil,
Mulann-Prolann, Oxxius, Quantel, Yenista, CNRS FOTON, ENSSAT, IUT-Lannion (Mesures Physiques), Lycée Le
Dantec (BTS Génie optique), ABRET, CAD22, Technopole Anticipa.
Diafir
Edixia
Le Verre Fluoré
Optinvent
CNRS EVC
CNRS IPR Photonique
BDI
Bretagne international
CCIR
Institut Maupertuis
MEITO
LANNION
BREST
RENNES
The Photonics Bretagne cluster has 42 members:
22 companies, 10 R&D centers and schools, 10 support agencies.
Not based in Bretagne: Thales Underwater Systems, DCNS, ONERA, ISL, Rhénaphotonics.
4
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Introduction
Chalcogenide Microstructured Fibers (EVC, PERFOS)
Four-wave Mixing Based Wavelength Conversion (FOTON)
Mid-IR Supercontinuum And Fourth-order Cascaded Raman Shift (ONERA)
Brillouin Fiber Laser (FOTON)
Conclusion and Perspectives
Outline
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
The Chalcogenide Photonic Crystal Fibers (PCFs) open the way
of new applications in the near and middle infrared region
GeSbS
As2Se3
Chalcogenide
glasses
Transmission extends
far in infrared region
A high nonlinear
refractive index n2 1 2
Why use chalcogenide fibers?
6
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Nonlinear applications:
-Supercontinuum generation in Mid IR: spectroscopy application
by LIDAR system
-Optical Transmission in singlemode or multimode guiding regime
(with small or large Mode Field Diameter)
-At Telecom wavelengths (Kerr, Brillouin and Raman effects):
Optical gates, wavelength conversion…
Passive functions:
-Sensors: a lot of chemical species has their fundamental vibration
in the Mid IR (CO2 detection)
And much more!!
Potential of applications
7
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Chalcogenide glass properties
8
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
-Water, oxides, carbon, bubbles and other impurities have to
be removed to improve chalcogenide fibre transmission
-Some distillations under vacuum are necessary to remove the
residual pollutants in order to obtain high purity glass.
Vaccum
pump
Liquid
nitrogen.
Silica
Ampoule
Sealing place
Elements
0
100
200
300
400
500
600
700
800
900
0 10 20 30 40 50
Time (hours)
Tem
pera
ture (
°C)
Heating and
reaction of
the elements
Homogenization
Condensation
of vapors
Quenching
100°C / min
Annealing
Cooling
Thermal treatment in a rocking furnace
Sulfur based glass Selenium based glass
Technological key point: glass purification
9
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Technological key point: glass purification
10
AsSe glass
-Good stability against crystallization
- Low loss (purification capability)
- Aging
n≈2.8 at 1,55µm tg ≈165°C n2~500*n2silica
The Purification steps are crucial to obtain low loss fiber:
High purity glass Unpurified glass
OH Oxydes OH
10
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
P
Neutral gas
arrival
Pressure
gas
system
Drawing
surrounding
wall Heating area
Diameter
measurement
Optical fiber
Tension
measurement drum
Drawing parameters :
Preform speed= 1mm/min
Drum speed= 5 m/min
Drawing temperature= 360°C
L> 50m
Drawing tower
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
nsilice
nair
neffectif
• Low cladding index
• nair < nsilica
• Design defined by d/
• Endessly singlemode (d/ < 0.45)
• Dispersion management
• Mode diameter less sensitive to
• High nonlinearity coefficient
• Photonic bandgap fiber
d
Why use microstructured fibers
12
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
• The losses decrease with the number of
rings
• For high index materials like Chalcogenide
glasses, three rings of holes are enough to
obtain waveguide losses lower than material
losses (~ 1dB/m)
Microstructured Chalcogenide Fibers: Properties
13
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Stack of capillaries
Tubes fabrication from
the rotationnal method
Microstructured
fiber
Stacking together capillaries and rods to form a preform with a solid central region
surrounded by an array of air holes which is then drawn down to form a PCF
Stack and draw technique (Old method)
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Capillaries
holes
Bubbles
Interstitial
holes
Capillaries
interfaces
During the jacketing process, microinhomogeneities
appear on the preform:
-Bubbles are due to the negative pressure
-Origin of the colour contrast at the
capillary interfaces is unclear: Crystals, very small
bubbles, volatile material deposition…
Other fabrication methods had to be developed to reach losses < 1dB/m
Main drawback of the method: losses greater than 15 dB/m
Stack and draw technique (Old method)
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Glass molded
on capillaries
1st step: mold fabrication
Microstructured
silica guides
Silica capillaries
Glass rod
Silica tube
2nd step: heating and flowing steps
hydrofluoric acid
3nd step: silica capillaries removal
AsSe preform
(Φ~16mm; L~5 cm
Molding technique (New method)
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Coefficient of thermal expansion:
Chalcogenide glasses Silica glass
[14 -25 ].10-6 K-1 >> 0.54. 10-6 K-1
Silica capillaries induce an important mechanical stress to the chalcogenide
glass
Chalcogenide glass breaking
With the right dimensions, the silica capillaries are more
flexible and do not induce chalcogenide glass breaking
Molding technique key point: Capillary thickness
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
- Background attenuation < 0.5 dB/m,
- [email protected] µm<50dB/km!!!
- OH peak attenuation < 3 dB/m
Multimode grapefruit AsSe PCF
PCF fabricated using the molding technique
18
0
1
2
3
4
5
1 3 5 7
Att
en
ua
tio
n (
dB
/m)
Wavelength (µm)
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
PCF fabricated using the molding technique
But also:
Endlessly singlemode fiber,
Suspended core fiber,
Small-core fiber,
Large-core fiber…
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
The large nonlinearity of chalcogenide
PCFs induces extremely strong Kerr,
Raman and Brillouin effects:
* γ~ 30 000 W-1km-1 demonstrated in 2010!
* Chalcogenide glass has very high negative
dispersion below 2µm
* Brillouin: ΔνB = 8.2 GHz
gB = 100 x times gB fused silica
* Raman:ΔνR = 9.8 THz
gR = 180 x times gR fused silica
Nonlinear optics in Chalcogenide PCF
Glasses n2Glass / n2SiO2
SiO2 1
As2S3 120
Ge15Sb20S65 140
GeSe4 400
As2Se3 650
n2 (m2/W)
Selenium based glasses
Oxide glasses
Sulfur based glasses
Fluoride glasses
10-17
10-18
10-20
10-21
20
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Introduction
Chalcogenide Microstructured Fibers (EVC, PERFOS)
Four-wave Mixing Based Wavelength Conversion (FOTON)
Mid-IR Supercontinuum And Fourth-order Cascaded Raman Shift (ONERA)
Brillouin Fiber Laser (FOTON)
Conclusion and Perspectives
Outline
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Goal: Signal processing at low power
LTF
LFIBER=1m
FA≈280µm
LTF
c~1m
A~5m
10cm 10cm
Asse Suspended-core Tapered Fiber
effAn 22Nonlinear Parameter: Aeff: effective area of the guided mode≈1µm2
n2: nonlinear refractive index≈500n2silica
= 46 000 km-1W-1 ≈ 2 km-1W-1 for standard silica fiber
≈ 70 km-1W-1 for ultra nonlinear silica PCF
A high value of enables to enhance nonlinear effect at low power
Key points:
-Ultra nonlinearity
-Low loss
Wavelength conversion by Four Wave Mixing
22
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
2010: Fiber 1 (presented at ECOC 2010)
٥ = 31 300 W-1km-1
٥ = 4.6 dB/m
٥ D = -820 ps/km-nm
٥ Insertion loss: 10 dB
2011: Fiber 2 (presented at ECOC 2011)
c~2 m
LF = 1 m
c~1.13 m
A~5 m
٥ = 46 000 W-1km-1
٥ = 0.9 dB/m
٥ D = -300 ps/km-nm
٥ Insertion loss: 4.2 dB
Mode adaptation reducing coupling losses
Wavelength conversion by Four Wave Mixing
23
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Wavelength conversion by four wave mixing
24
Definition of FWM efficiency :
1
2
FWMFWM
P
P
• PFWM1 : Peak power of FWM signal at the output of AsSe fiber
• P2 : Power of CW pump signal launched into the AsSe fiber
1 + 2 = 3+ 4
1 2
FWM1 FWM2
Pulsed pump
ConvertedSignal
CW pump
3 1 2 4
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Wavelength conversion by four wave mixing
25
10 GHz clock signal
50:50
Coupler
BPF Attenuator EDFA
PC EDFA
Clock
signal
CW
Laser
PwM
AsSe fiber
Free-space
Coupling 10%
90%
PC Optical Spectrum
Analyser
Powermeter
10 GHz or
42.7 GHz
42.7 GHz clock signal
Time (ps)
5 ps
30
20
10
0
Po
we
r (m
W)
0 10 20 40 30 50 60 70
Time (ps)
8.3 ps
0 20 40 80 60 100 120
30
20
10
0 Po
we
r (m
W)
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Wavelength conversion (10GHz)
Δ
(nm)
Pin.10G
(mW)
Pin.CW
(mW)
PFWM1
(mW)
FWM1
(dB)
FWM2
(dB)
1.9 8.9 8.1 0.18 -5.6 -21
26
1 1.5 2 2.5 3 3.5 4 4.5 -30
-25
-20
-15
-10
-5
0
Wavelength detuning Δ (nm)
Eff
icie
nc
y (
dB
)
(c)
Experiment
Simulation
1544 1548 1552 1556 1560 1564 -70
-60
-50
-40
-30
-20
-10
0
Wavelength (nm)
Inte
ns
ity (
a.u
)
CW pump 2
Pulsed pump 1
Anti-Stokes
FWM1
FWM2
FWM3
Stokes
(a)
1546 1548 1550 1552 1554 1556 1558 1560
-60
-50
-40
-30
-20
-10
0
= 1.9 nm = 2.2 nm = 2.4 nm = 2.8 nm
Wavelength (nm)
Inte
ns
ity (
a.u
)
(b)
1 = 1552.7 nm;
2 = 1 + Δ
Improvement of 21 dB comparing to the previous fiber
17.0 mW
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Wavelength conversion (42.7GHz)
Δ
(nm)
Pin.40G
(mW)
Pin.CW
(mW)
PFWM1
(mW)
FWM1
(dB)
FWM2
(dB)
6.1 10.1 7.1 0.026 -17.5 -36
27
Wavelength (nm)
Inte
ns
itu
y (
a.u
)
1535 1540 1545 1550 1555 1560 1565
-60
-50
-40
-30
-20
-10 42.7GHz 1 CW pump
2
FWM1
FWM2
(b)
1535 1540 1545 1550 1555 1560 1565
-50
-40
-30
-20
-10
0
10
Wavelength (nm)
Inte
ns
ity (
a.u
)
(a)
4 4.5 5 5.5 6 6.5 7 7.5 8 8.5
-35
-30
-25
-20
-15
Wavelength detuning Δ (nm)
Eff
ica
cit
y (
dB
)
Experiment
Simulation
(c)
CW 42.7 GHz
17.2 mW
1 = 1549.9 nm;
2 = 1 + Δ
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION 28
Solution: use a singlemode fiber (results will be presented at OFC 2012)
Input PRBS signal Output PRBS signal
20
10
0
0 40 20 80 60 Po
we
r (m
W)
Time (ps) 0 40 20 80 60
30
20
10
0
Po
we
r (m
W)
Wavelength conversion by four wave mixing
Demonstration of efficient FWM at 10 GHz and 42.7 GHz
with a chalcogenide fiber
Optical power compatible with telecom applications
high speed signal processing?
Closed eye-diagram with a PRBS RZ signal because of
the multimode behavior of the fiber
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Introduction
Chalcogenide Microstructured Fibers (EVC, PERFOS)
Four-wave Mixing Based Wavelength Conversion (FOTON)
Mid-IR Supercontinuum And Fourth-order Cascaded Raman Shift (ONERA)
Brillouin Fiber Laser (FOTON)
Conclusion and Perspectives
Outline
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Raman shift by pumping at 2 µm in ns regime
30
3 Raman shifts at :
2092 nm
2205 nm
2330 nm
Pumping away from ZDW
Normal dispersion regime 2000 2100 2200 2300 2400
-60
-50
-40
-30
-20
-10
0
No
rma
lize
d I
nte
nsity (
dB
)
Wavelength (nm)
1 W
2 W
3 W
5 W
L = 4.4 m
Splicer n°1
UHNA
As38Se62 fiber
Optical
Spectrum
Analyser
2µm laser
source
Suspended core fiber
dc = 3.5 µm
Zero Dispersion Wavelength ≈ 3.15 µm
10 ns pulses
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION 31
2000 2100 2200 2300 2400 2500
-60
-30
0
Experimental data Simulation
Norm
aliz
ed
In
ten
sity (
dB
)
Wavelength (nm)
Raman shift by pumping at 2 µm in ns regime
L = 1.8 m
P = 11 W peak power
4 orders Raman shifts in AsSe fiber
gR = 2.3 10-11 m/W @ 1.55 µm
gR = 1.8 10-11 m/W @ 2 µm
Measurement of the Raman
gain coefficient
Same set-ut
Low injected peak power
(1 Raman shift in 0.7 m)
Comparison between experimentation
and simulation
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION 32
1200 1400 1600 1800 2000 2200 2400 2600
-60
-50
-40
-30
-20
-10
0
No
rma
lise
d P
ow
er
(dB
)
Wavelength (nm)
150 W
25 W
• At low peak power (25W injected) :
• Multiple peaks around the pump wavelength
• Satisfy the energy conservation relation
• At high peak power (150W injected)
• Supercontinuum generation
• Broadening stops at 2600 nm
signalidlerpompe 2
CONFIAN
Mid-IR Supercontinuum by pumping in ps regime
Source
Singlemode mode-locked fiber source at 1960nm
3.5 ps / 11.2 MHz / 9 kW peak power
AsSe tapered suspended core fiber
ZDW ~2 µm in the waist
More details see Paper 8237-113 (Poster yesterday)
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Introduction
Chalcogenide Microstructured Fibers (EVC, PERFOS)
Four-wave Mixing Based Wavelength Conversion (FOTON)
Mid-IR Supercontinuum And Fourth-order Cascaded Raman Shift (ONERA)
Brillouin Fiber Laser (FOTON)
Conclusion and Perspectives
Outline
Page 34
DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Chalcogenide Brillouin Fiber Laser
34
Silica
(Song) [1]
AsSe
(Song) [1]
AsSe
(Florea) [2]
AsS
(Florea) [2]
AsSe
(Foton)
Refractive index, n 1.47 2.81 2.81 2.45 2.81
Mode effective area, Aeff [m²] 6.78E-11 3.94E-11 6.31E-11 1.39E-11 8E-12
Losses [dB/m] 0.001 0.84 0.9 0.57 1.0
Length L [m] 2 5 5 10 3
Effective length, Leff [m] 2 3.23 3.1 5.6 2.16
Brillouin gain coefficient, gB [m/W] 4.40E-11 6.10E-09 6.75E-09 3.90E-09 5.60E-09
Brillouin gain measured in suspended-core chalcogenide fiber 6.10-9 m/W
(2 orders of magnitude higher than in SMF28 fibers)
[1] K.Y. Song et al. , Highly efficient Brillouin slow and fast light using As2Se3 chalcogenide fiber. Optics Express,
14(13) :5860–5865, 2006.
[2] C. Florea et al., Stimulated Brillouin scattering in single-mode As2S3 and As2Se3 chalcogenide fibers. Optics
Express, 14(25) :12063–12070, 2006.
Brillouin characterization
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Chalcogenide Brillouin Fiber Laser
35
Nonresonant pumping of the cavity No need for servo-locking
Laser threshold 22 mW with an efficiency of 30%
Laser linewidth < 4 kHz (Resolution of self-heterodyne bench)
Configuration of the ring cavity Laser
threshold
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Relative Intensity Noise of the BFL
٥ RIN reduction of 5 dB around the relaxation frequency peak
٥ Excess intensity noise for low frequencies due to unstable operation
(polarization) and reinjection of pump wave due to Fresnel reflection
٥ Multiple peaks for low frequencies laser sensitive to environmental noise
Chalcogenide Brillouin Laser
36
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Chalcogenide Brillouin Laser
NOISE PERFORMANCE OF THE BFL
37
٥ Around 6 dB reduction of the BFL frequency noise as compared to its pump laser [3]
٥ Important noise contribution for low frequencies BFL very sensitive to environmental
noise and not properly packaged (Same behaviour with a SMF-28 BFL )
Frequency noise of the BFL
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Introduction
Chalcogenide Microstructured Fibers (EVC, PERFOS)
Four-wave Mixing Based Wavelength Conversion (FOTON)
Mid-IR Supercontinuum And Fourth-order Cascaded Raman Shift (ONERA)
Brillouin Fiber Laser (FOTON)
Conclusion and Perspectives
Outline
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
-The interest of chalcogenide glasses is the association of their mid-infrared transmission with :
- Their highly nonlinear properties
- Photonic crystal fiber properties
- Stack and draw and molding fabrication process have been compared. The losses of the fibers prepared
by the molding method are close to the material losses.
- Low loss have been obtained in a multimode 6-hole suspended core PCF:
- 0.4 dB/m at 1.55 µm, less than 50 dB/km at 3.7 µm!
- Weak Se-H absorption band, and only 3 dB/m at 2.9 µm (O-H band)
- Singlemode behavior of chalcogenide PCF in Mid-IR:
- AsSe PCF at the telecom wavelengths (0.8 dB/m)
-Record high ~ 30 000 W-1km-1 demonstrated in 2010 in fibers, ~ 46 000 W-1km-1 demonstrated
this year in « tapered » fibers
Conclusion and Perspectives (1/2)
39
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
Conclusion and Perspective (2/2)
40
٥ Demonstration of the wavelength conversion for telecommunications
signal at 10 GHz and 42.7 GHz.
٥ Generation of Raman stokes band and Four wave-mixing
٥ Mid-IR supercontinuum generation
٥ Brillouin chalcogenide fiber laser demonstrated
٥ High potential for high-speed optical signal processing but also for
passive applications (Mid-IR sensors,power delivery…)
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DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
References and Aknowledgement
41
The authors would like to acknowledge:
French ANR (Confian, Futur), FUI (ATOS) and DGA.
They also want to thank the following researchers for their active participation in this
work (see references in the paper):
Kenny Hey Tow, Matthieu Duhant, Sy Dat Le, Perrine Toupin, Quentin Coulombier,
William Renard, Duc Minh Nguyen, Monique Thual, Laurent Bramerie.
Page 42
PERFOS : R&D platform of Photonics Bretagne
DEVELOPING CUSTOM MICROSTRUCTURED FIBERS FOR YOUR APPLICATION
PLEASE COME AND VISIT US AT OUR BOOTH (BOOTH NUMBER: 2111)!!!
DAVID MÉCHIN ([email protected] ) WWW.PHOTONICS-BRETAGNE.COM/PERFOS
Perfos
R&D platform of Photonics Bretagne
11 rue Louis de Broglie
22300 Lannion – France