CO2 Laser Fusion Splicing Between PBGF and SMF

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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
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Purpose

• 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)
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My Project Description

• 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

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Project Set-up
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Project Set-up
CO2
HeNe
ZnSe Lens
Clamps with Fibers
Combiner
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ZnSe Lens
Lasers are passing through the center of the lens
Lasers are not centered
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Fiber Set-up
Power (in mW) 10 (Power dBm)/10
Butt Coupled fibers
Fiber connected to Power meter
Fiber connected to IR Laser 2.3dBm (1.69 mW)
Clamp on translation stage
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Procedure

• 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).

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Splice at 3V for 1 minute or until transmission
through fibers drops.
Pre-heating for 20 sec. at 0.65V

• Activate CO2 laser using Labview program, and
  observe fiber transmission vs. time.

Power
Power Drop
1.95 dBm

• Calculate Splice Loss.

-2.12dBm
Splice complete
-5.1 dBm
Time
Stuffing Stroke
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Procedure (cont.)

• Check splice strength Break Radius.

BR (L1 L2) / (2p)
L1 L2 circumference
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Challenges

• Problem 1 Fiber Slipping during Stuffing
  Stroke.
• Problem 2 Fragile splices. - sticky rubber
  on clamps - fiber length

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ZnSe windows
Translation Stage Fixed Clamp
ZnSe Lens
ZnSe Window
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Results

• Break Radius 0.76 cm
• Break Radius 1.37cm 0.27cm

• In Vacuum Chamber without ZnSe windows at
  atmospheric pressure
• Splice Loss
• -0.07 dBm gt Perfect splice
• With ZnSe windows in
• Splice Loss 0.55 dBm 2.235 dBm

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Future of the project

• 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.

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Special Thanks )

• 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