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Single-mode-fiber 1 x N directional coupler.
Optics Letters
|August 29, 2009
Summary
Researchers developed an adjustable fiber optic directional coupler with uniform output. This new silicon V-groove fabrication technique enables efficient, polarization-independent coupling for fiber data-bus systems.
Area of Science:
- Optoelectronics
- Fiber optics
Background:
- Directional couplers are essential components in optical communication systems.
- Existing devices often face limitations in adjustability and output uniformity.
Purpose of the Study:
- To develop an adjustable single-mode-fiber multiterminal directional coupler.
- To achieve efficient coupling and uniform terminal output over a wide range of coupling coefficients.
Main Methods:
- Utilized silicon V-groove substrates for fabricating arrays of evanescently coupled taps on single-mode fibers.
- Developed a new fabrication technique for creating multiterminal directional couplers.
Main Results:
- Demonstrated efficient coupling and uniform terminal output.
- Achieved a highly directional and polarization-independent coupler.
- Reported low excess loss as 0.09 dB per terminal in a 1x7 device.
Conclusions:
- The developed fabrication technique offers a scalable solution for producing multiterminal directional couplers.
- The device is suitable for applications in fiber data-bus systems and tapped delay lines for broadband signal processing.
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