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Updated: Jul 13, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Compact polarization rotators for integrated polarization diversity in InP-based waveguides
Daryl M Beggs1, Michele Midrio, Thomas F Krauss
1School of Physics & Astronomy, University of St Andrews, North Haugh, St Andrews, KY16 9SS, UK. daryl.beggs@st-andrews.ac.uk
Optics Letters
|August 3, 2007
Summary
We developed a compact polarization converter using angled waveguides. This device achieves high efficiency and broadband operation, making it ideal for integrated photonic circuits.
Area of Science:
- Photonics and Optical Engineering
- Materials Science
Background:
- Integrated photonics requires efficient polarization control.
- Existing polarization converters often suffer from large footprints or narrow bandwidths.
Purpose of the Study:
- To design, fabricate, and operate a compact and efficient polarization converter.
- To demonstrate its suitability for integrated polarization diversity schemes.
Main Methods:
- Utilized the Indium Phosphide/Indium Gallium Arsenide Phosphide (InP/InGaAsP) material system.
- Integrated design principles from mode evolution and birefringent devices.
- Fabricated devices with angled waveguides.
Main Results:
- Achieved a short device length (<50 micrometers).
- Obtained high insertion efficiency (81%+/-19%, 1 dB insertion loss).
- Demonstrated broadband operation with >15 dB polarization conversion over a 100 nm wavelength range.
Conclusions:
- The developed polarization converter meets key specifications for integrated photonic applications.
- Its compact size, high efficiency, and broadband performance are advantageous.
- It is a strong candidate for polarization diversity schemes in integrated systems.
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