INTERNSHIP PRESENTATION
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Transcript of INTERNSHIP PRESENTATION
INTERNSHIP PRESENTATION
DEBASMIT DASENROLLMENT NO. – 10115039
BATCH E3
DETAILS ABOUT MY INTERNSHIPTYPE – RESEARCH INTERNSHIPPLACE – ECOLE POLYTECHNIQUE DE
MONTREALFIELD – PHOTONICSGUIDE – DR. RAMAN KASHYAPLAB- ADVANCED PHOTONICS CONCEPTS
LABORATORYDURATION – 13TH MAY TO 19TH JULY, 2013
CONTENTS OF MY INTERNSHIPFABRICATION OF A 4-PORT OPTICAL FIBER
COUPLEREXPERIMENTAL AND THEORITICAL
ANALYSIS OF SURFACE PLASMON DEVICES (SPR) BASED ON OPTICAL FIBER
FABRICATION OF A 4-PORT OPTICAL FIBER COUPLERAIM OF THIS PROJECT IS TO BUILD A
COUPLER THAT CAN BE USED MULTIPURPOSELY FOR DIFFERENT PROJECTS IN THE FUTURE.
I APPLIED THE COUPLER TO OBTAIN THE REFLECTION AND TRANSMISSION SPECTRUM OF A TILTED FIBER BRAGG GRATING.
DETAILS ON THESE IN THE COMING SLIDES……
FIBER OPTIC COUPLER
Coupler used to direct light into the Fiber Bragg Grating.LC=Coupling Length ; LW = Waist Length ; LT = Taper length
Plot of power P1-3 (red) P2-4 (green) with distance along coupling length
P1-3 (Power in wave guide 1 to 3) = cos2(kz) P2-4(Power in wave guide 2 to 4) = sin2(kz)
FBG and tilted FBGResonance condition for FBG λB = 2nt
For tilted FBG the condition holds as λB = 2nt cos (x) where x is the angle of tiltBut why is the tilted FBG?Because my fiber is DCF (double clad fiber)
Schematic of the Coupler I am to produce
StepsEtching of two DCF fibers around 15 cm
lengthTwisting of the two fibers along the etched
portion.Fixing the coupler to a platform to make it
ready for measurementsCharacterization of the coupler and
observing the spectrum of the tilted FBG
DCF before being etched DCF after being etched
CharacterizationExcessive Loss = -10 log(P1+P2/Pin)CR = P2/P1+P2 x 100 % (Coupling Ratio)For 6 Twists – Pin= 12.35dBm P1=10.45 dBm P2=-32.45 dBm So excessive Loss = 1.5497 dB CR=0.005688 %
Reflection and Transmission Spectrum
SURFACE PLASMON RESONANCEAIM OF THIS PROJECT IS SIMULATION
AND ANALYSIS OF SPR ON A NOVEL H-SHAPED FIBER
SIMULATION HAS BEEN DONE IN MATLABPURPOSE OF SIMULATION IS TO ANALYSE
AND COMPARE WITH EXPERIMENTAL RESULTS
PHENOMENON OF SPR
k*ng *sinθ = k((ns2*εm)/( ns
2 + εm ))^0.5
MOMENTUM TRANSFER CONDITION
APPLICATIONAs a biosensor or a chemical sensorAs refractive index of sensing medium changes so
will the resonance wavelengthSo the resonance wavelength can plotted with
refractive index and this calibration is used to create biosensor
It can indirectly be used to measure concentration of analyte which perturbs refractive index
ADVANTAGE : Very high sensitve sensors ~ 3000 nm/RIU . Apt for the nano world.
The Special H-shaped fiber
Why H-shaped Fiber?Birefringent fiber with elliptical coreTwo orthogonal single modes with no
interference in visible region.Can be used to measure two quantities
simultaneouslyBut for now analysis is done for one axis that
is the axis along the cleavage….
N-Layer Model ParametersN=3 for our casesn1=core n2=metal n3=dielectric sensing
medium Core diameter =10 nm Metal thickness (gold)
=50 nm and Dielectric thickness = 25 nm
0.4 0.5 0.6 0.7 0.8 0.9 10.1
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Wavelength (nm)
Nor
mal
ised
Pow
er
THANK YOU !!
SPECIAL THANKS TO MITACS FOR FUNDING THE INTERNSHIP