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Fully-guided polarization-correlated photon pairs at 1560 nm from a type-II SPDC-based source.
Optics Letters
|February 1, 2024
Summary
Researchers developed a bright, narrowband source for spectral and polarization-correlated photon pairs, crucial for quantum technology and secure communication. This MgO:ppLN waveguide source offers high brightness and reliability for long-distance quantum networks.
Area of Science:
- Quantum technology
- Quantum optics
- Photonics
Background:
- Spectral and polarization-correlated biphotons are essential for quantum information processing.
- Developing reliable sources for these photon pairs is a key challenge in quantum technology.
Purpose of the Study:
- To report a novel, bright, narrowband source of spectral and polarization-correlated orthogonal photon-pairs.
- To investigate the generation of high rates of correlated orthogonal twin photons from a type-II spontaneous parametric down-conversion (SPDC) source.
Main Methods:
- Utilized a fiber-pigtailed, type-II quasi-phase-matched, MgO-doped periodically poled lithium niobate (MgO:ppLN) ridge waveguide.
- Operated the source at telecom wavelengths around 1560 nm.
Main Results:
- Achieved a high spectral brightness of approximately 5×10^6 photon pairs/s/mW/nm.
- Obtained a coincidence-to-accidental ratio (CAR) of approximately 427.
- Characterized a narrow emission bandwidth of approximately 2.4 nm.
Conclusions:
- The developed MgO:ppLN waveguide source provides a reliable and efficient method for generating spectral and polarization-correlated photon pairs.
- Its compact and narrowband characteristics make it suitable for commercial quantum communication systems, particularly for long-distance transmissions.
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