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Sagnac-loop phase shifter with polarization-independent operation.
Tien Tjuen Ng1, Darwin Gosal, Antía Lamas-Linares
1Centre for Quantum Technologies/Department of Physics, National University of Singapore, Singapore.
The Review of Scientific Instruments
|February 2, 2011
Summary
This study demonstrates a novel polarization-independent phase shifter for quantum information. The bulk-optic device maintains arbitrary polarization states, crucial for advanced photonic applications.
Area of Science:
- Optics
- Quantum Information Science
- Photonics
Background:
- Photonic quantum information applications require precise control over light polarization.
- Existing phase shifters can be polarization-dependent, limiting their utility.
- Development of polarization-independent optical components is essential for robust quantum technologies.
Purpose of the Study:
- To demonstrate a bulk-optic, polarization-independent phase shifter.
- To integrate this phase shifter into an optical switch for quantum information processing.
- To evaluate the device's performance in terms of contrast and switching speed while maintaining polarization integrity.
Main Methods:
- Utilized a transverse electro-optic modulator within a Sagnac-type loop.
- Incorporated Faraday rotators to achieve direction-dependent polarization rotation.
- Combined the Sagnac loop with a Mach-Zehnder interferometer to create an optical switch.
Main Results:
- Achieved a polarization-independent phase shifter.
- Demonstrated an optical switch with 96% on/off contrast.
- Exhibited a fast switching time of 1.6 nanoseconds.
- Confirmed the device maintains arbitrary polarization states.
Conclusions:
- The demonstrated bulk-optic phase shifter is suitable for photonic quantum information applications.
- The polarization-independent nature and high performance of the optical switch are significant advancements.
- This device offers a robust solution for manipulating quantum information encoded in photons.
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