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Updated: Jun 4, 2026
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Compact polarization rotator on silicon for polarization-diversified circuits
Long Chen1, Christopher R Doerr, Young-Kai Chen
1Bell Laboratories, Alcatel-Lucent, Holmdel, New Jersey 07733, USA. long_l_chen@alcatel‑lucent.com
Optics Letters
|February 18, 2011
Summary
We developed a silicon polarization rotator for diverse circuits. This device achieves over 90% conversion efficiency with low loss, enhancing polarization control in optical systems.
Area of Science:
- Photonics and Optical Engineering
- Materials Science (Silicon Photonics)
Background:
- Polarization control is crucial for advanced optical circuits.
- Existing polarization rotators often lack broadband performance or require complex fabrication.
- Silicon photonics offers a scalable platform for integrated optical components.
Purpose of the Study:
- To demonstrate a novel silicon-based polarization rotator.
- To achieve high polarization-conversion efficiency and low insertion loss over a broad wavelength range.
- To integrate the rotator with a polarization beam splitter for enhanced performance in polarization-diversified circuits.
Main Methods:
- Utilized adiabatic mode evolution on a silicon platform.
- Designed and fabricated a compact polarization rotator with a device length of 420 μm.
- Integrated the rotator with a broadband polarization beam splitter based on cascaded directional couplers.
Main Results:
- Achieved polarization-conversion efficiency exceeding 90% for the rotator.
- Demonstrated insertion loss below 1 dB over an 80 nm wavelength range.
- Enhanced polarization conversion extinction ratio over 30 dB with total insertion loss below 1.5 dB over a 60 nm spectral range when combined with the beam splitter.
Conclusions:
- The demonstrated silicon polarization rotator is effective for polarization-diversified circuits.
- The device offers excellent efficiency and low loss across a broad spectral range.
- Integration with a polarization beam splitter further improves extinction ratios, paving the way for advanced silicon photonic integrated circuits.
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