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Newly discovered silicon nitride quantum emitters hold great promise for industrial-scale quantum photonic applications. We assess the performance of intrinsic room-temperature SiN single-photon emitters for quantum key distribution, showcasing their exceptional brightness and single-photon purity.
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This content will become publicly available on June 20, 2026
Room-temperature high-purity single-photon emission from carbon-doped boron nitride thin films
Hexagonal boron nitride (h-BN) has emerged as a promising platform for generating room temperature single photons exhibiting high brightness and spin-photon entanglement. However, improving emitter purity, stability, and scalability remains a challenge for quantum technologies. Here, we demonstrate highly pure and stable single-photon emitters (SPEs) in h-BN by directly growing carbon-doped, centimeter-scale h-BN thin films using the pulsed laser deposition (PLD) method. These SPEs exhibit room temperature operation with polarized emission, achieving ag(2)(0) value of 0.015, which is among the lowest reported for room temperature SPEs and the lowest achieved for h-BN SPEs. It also exhibits high brightness (~0.5 million counts per second), remarkable stability during continuous operation (>15 min), and a Debye-Waller factor of 45%. First-principles calculations reveal unique carbon defects responsible for these properties, enabled by PLD’s low-temperature synthesis and in situ doping. Our results demonstrate an effective method for large-scale production of high-purity, stable SPEs in h-BN, enabling robust quantum optical sources for various quantum applications.
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- PAR ID:
- 10610645
- Publisher / Repository:
- AAAS
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 11
- Issue:
- 25
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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