Transcript CO2 Laser Fusion Splicing Between PBGF and SMF

CO2 Laser Fusion Splicing
Between PBGF and SMF
Dana Cristea
Bridgewater College / KSU
Physics Research 2006
Other members of LUMOS lab:
Kristan Corwin, Rajesh Thapa, Kevin Knabe, Andrew Jones
Purpose
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What? ~ Sealing hollow optical fiber
containing acetylene gas.
Why? ~ Frequency metrology, atomic
clocks and quantum/atom optics
Who else? ~ P.S. Light, F. Couny,
and F. Benabid.
Single Mode Fiber
(SMF)
Photonic Bandgap
Fiber (PBGF)
My Project Description
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Status of Project:
- splices made in air;
- new apparatus build, untested.
My Goal:
- make splices in vacuum.
Results:
- Improved splices in air.
Major Challenges:
- fiber slipping and sticking to clamps;
- fiber length.
Future Directions
Project Set-up
Project Set-up
HeNe
ZnSe Lens
Clamps with Fibers
Combiner
CO2
ZnSe Lens
Lasers are passing
through the center
of the lens:
Lasers are not
centered:
Fiber Set-up
Power (in mW) = 10 (Power dBm)/10
“Butt Coupled” fibers
Fiber connected to Power meter
Clamp on
translation stage
Fiber connected to IR Laser
~2.3dBm (1.69 mW)
Procedure
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Secure fibers in clamps
Overlap lasers and align them onto
fibers
“Butt Couple” the fibers until maximum
transmission obtained.
Apply “Stuffing Stroke” ~ pushing fibers
together until transmission drops ~3-4
dBm (fibers shrink during splice).
Splice at 3V for 1 minute or
until transmission through
fibers drops.
Pre-heating for 20
sec. at 0.65V
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Power
Power Drop
Activate CO2 laser
using Labview
program, and observe
fiber transmission vs.
time.
+1.95 dBm
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-2.12dBm
Splice complete
-5.1 dBm
Stuffing Stroke
Time
Calculate Splice Loss.
Procedure (cont.)
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Check splice strength ~ “Break Radius.”
BR = (L1+ L2) / (2*π)
L1+ L2 = circumference
Challenges
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Problem #1: Fiber Slipping during Stuffing
Stroke.
Problem #2: Fragile splices.
- sticky rubber on clamps
- fiber length
ZnSe windows
Translation Stage
ZnSe Window
Fixed Clamp
ZnSe Lens
Results
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In Vacuum Chamber without
ZnSe windows at
atmospheric pressure
Splice Loss
-0.07 dBm => “Perfect” splice
With ZnSe windows in
Splice Loss
+0.55 dBm
+ 2.235 dBm
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Break Radius
+0.76 cm
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Break Radius
+1.37cm
+0.27cm
Future of the project
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Splice SMF to SMF inside vacuum
chamber with air in and lower power.
Splice SMF to SMF with air pumped
out.
Splice SMF to PBGF and create
acetylene cell.
Special Thanks =)
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Dr. Kristan Corwin
Mr. Mike Wells
LUMOS Group (Rajesh Thapa, Kevin
Knabe, and Andrew Jones)
Dr. Larry Weaver
NSF/REU/Physics Department
Aaron Pung, Matt Wood, and Greg
Johnson