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Updated: Mar 1, 2026

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Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source
Published on: April 4, 2017
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Mid-infrared entanglement in 220 nm silicon
Optics Letters
|February 27, 2026
Summary
Researchers developed a novel mid-infrared photon-pair source using standard 220nm silicon, achieving high performance for quantum technologies. This work demonstrates the first integrated mid-infrared entanglement, paving the way for advanced quantum applications.
Area of Science:
- Quantum optics
- Silicon photonics
- Mid-infrared technologies
Background:
- Silicon photonics is a key platform for developing quantum technologies.
- Previous mid-infrared quantum optics utilized a 340nm silicon layer height.
Purpose of the Study:
- To implement a novel photon-pair source using industry-standard 220nm silicon.
- To demonstrate integrated mid-infrared entanglement.
Main Methods:
- Utilized 220nm silicon layer height for device fabrication.
- Characterized a novel photon-pair source.
- Generated and verified a Bell state for entanglement.
Main Results:
- Achieved a peak coincidence-to-accidental ratio (CAR) of 20.9±2.9.
- Measured a net rate of 0.63±0.02 Hz.
- Inferred a source efficiency of 2.85±0.04 MHz W-2.
- Generated a Bell state with a fidelity of 94±2%.
Conclusions:
- Demonstrated the first integrated mid-infrared entanglement.
- The 220nm silicon platform is suitable for advanced quantum optics.
- The novel photon-pair source shows significant potential for quantum information processing.
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