FORC research updates presented at Research Retreat 2016

1. FORC Research Updates
2016
FORC Research Retreat, Morib
11 – 13 November, 2016
R E S E A R C H C E N T E R

2. FORC focuses on design, fabrication and
characterization of specialty optical fiber
and its application
• Rare-earth doped fibers
• Microfiber
• FBG sensors
• LPG sensors
• SPR sensors
• Polymer PCF
• Optical Sensor Network
• Standard MCVD
• Solution Doping, Chelate Delivery
• Pulling Tower
• OSA
• Beam Profiler, Preform Profiler
Fabrication and Characterization Facilities
About us
R E S E A R C H C E N T E R
Simulation and Modelling
People
2 Professors, 1 Associate Professor,
2 Senior Lecturers, 3 Post-docs, 7 PhD,
9 M.Eng.Sc.

3. Sensors Waveguides
Active
Devices
Passive
Devices
O P T I C A L F I B E R FA B R I C AT I O N T E C H N O LO G Y
MCVD Pulling Tower FBG writing Fiber Taper
M AT E R I A L S C I E N C E S

4. Sensors
• FBG & LPG
• Flat Fiber
• Tapered Fiber
• Doped
Dosimeter
• PCF Dosimeter
Waveguides
• Mid infra-red
• Modified Silica
Host
• Polymer MOF
Active Devices
• S-band
Amplifier
• New Band
Amplifier
• Visible
Wavelength
Fiber Lasers
Passive Devices
• Optical Filter
• Tapered Fiber
• Wavelength
converters
• Optical CDMA
encoder
Sensors Waveguides
Active
Devices
Passive
Devices
O P T I C A L F I B E R FA B R I C AT I O N T E C H N O LO G Y

5. Optical Sensor Networks
Fiber-to-the-Home
Radiation Dosimetry
Optical Communication Systems
OPTICAL FIBER APPLICATIONS

6. 2014 2015 2016 2017 2018
PROJECT TIMELINES
S-BAND AMPLIFIER
NEW-BAND AMPLIFIER NEW-BAND FIBER NEW-BAND FIBER DEVICES
MICRO-FIBER
FBG OPTICAL CDMA (FRGS)
MICRO-FIBER DEVICES
LPG SENSOR NETWORK (ERGS)
NANOPARTICLE FIBER (FRGS)
BISMUTH FIBER (FRGS)
DOSIMETRY (UM-HIR)
DOSIMETRY OSL & RL (PRGS)
DOSIMETRY TL (FRGS) DOSIMETRY OSL & RL (CRADLE)
POLYMER MOF
DAS SPECIALTY FIBER DAS SYSTEM
OFDMA PON

7. New Optical Communication Band
Amplifier
• S-band amplifier
• New band amplifier
@ 1700 nm
• Silica host doped
with
• Erbium
• Thulium
• Bismuth
• Glass modifier
• Aluminium
• Gallium
• Barrium
Transmission Fiber
• Silica host
• Photonic Crystal Fiber
• Modified Silica host
Collaborative Project
7
Waveguide
Imperfection
Attenuation(dB
km-1)
0.01
0.05
0.1
1
0.5
10
50
100
5
0.8 1.0 1.2 1.4 1.6 1.8 2.2 2.4
Wavelength (µm)1stWindow(early80`s)
2ndWindow(mid80`s)
CandLWindow(1996)
S-BandWindow
Experimental Infra-red
Absorption
PossibleNewWindow

8. In-Situ Solution Doping
in-situ solution doping. Bi(NO3)3.5H2O solution is delivered to the tube after soot
deposition followed by oxidation, sintering and collapse to a preform.

9. New Band
P23 – Solution doping, Modifier: Al
P90 – Solution doping (salt), Modifier: Al
0
5
10
15
20
25
30
35
0 1 2 3 4 5 6 7
Amplitude(dBm)
Length (m)
Gain P90_125um Gain P23 NF P90_125um NF P23
Comparison of Gain and NF of two Tm doped fiber with different solution doping agents.

10. Bismuth-doped Fiber
• The ranges 1150 – 1500 and 1650 – 1750 nm of the spectral
window 1100 – 1800 nm are not covered by rare-earth fiber
lasers and amplifiers.
• Bismuth-doped optical fibers feature a broad luminescence
spectrum.
• The optical and lasing properties of Bi-doped fibers are greatly
influenced by fiber core composition, Bi concentration, and
fabrication technique.
• Optical fiber amplifier for GPON extender with simultaneous
operating wavelengths 1310 nm and 1490 nm.
• P2O5 doping of the fiber core leads to the appearance of a band
peaking in the region 1300 – 1350 nm.
• Bi concentration is < 200 ppm to avoid clustering.
• Fabrication with MCVD-in situ solution doping.

11. Bismuth-doped Fiber
Main emission peaks for different Bi-doped fibers

12. 0
5
10
15
20
25
30
35
600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700
Absorption(dB)
Wavelength (nm)
NTT Bi7 Bi8
Absorption of Bismuth doped fiber

13. -70
-60
-50
-40
-30
-20
1250 1300 1350 1400 1450 1500 1550
Amplitude(dBm)
Wavelength (nm)
Emission of Bismuth doped fiber
808 nm pump with 105 mW power

14. Dosimetry is a key monitoring technique for
safe and acceptable use of radiation in
different fields such as
Optical Fiber Radiation Dosimeter
Personal monitoring
Calibration high energy machines
Measuring the dose in small inaccessible
places in the body etc.
Fig: Dose
measurement
using TLD in
radiotherapy
Note: The OSL process is similar to the TL process except that the
trapped electrons are released optically and not thermally.
Fig : Schematic outline of OSL fiber
dosimetry system.
Thermoluminescence Dosimeter (TLD)
Optically Stimulated Luminescence Dosimeter
(OSL)
Fig : Schematic outline of TL fiber
dosimetry system.

15. RL Dosimetry System
Fig: Optical fiber-coupled OSL readout system
using Al2O3:C as a sensor
Main components of
RL/OSL dosimeter reader
are:
Sensor Crystal
Optical Detection
System, and
Signal Processing
Electronics

16. THEORY
Radioluminescence
1. Electron-hole pairs generated upon ionizing radiation
2. Radioluminescence is generated due to radiative recombination of the
electron/hole pairs at recombination centers

17. LINAC, Varian 2100CD
Grooves are drilled in some of the solid water slabs to house
the dosimeter probes.
Example of measurement setup Data aquisition
RADIOLUMINESCENCE
METHODS : IRRADIATION

18. Cylindrical Fiber
Results (RL):
Fig: RL as seen on data acquisition software (Co-60
source)

19. Cylindrical Fiber
Results (RL):
Fig: Linearity of RL graph for
SiO2:Ge at different dose rates
Fig: RL graph for SiO2:Ge at different dose rates

20. 0
5000
10000
15000
20000
0 100 200 300 400 500 600 700 800
Fig: RL response at different absorbed dose
Cylindrical Fiber
Results (RL):
Time (s)
Photoncounts

21. Fig: Linearity of Total counts vs Absorbed Dose
Cylindrical Fiber
Results (RL):