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Abstract Entanglement plays a vital role in quantum information processing. Owing to its unique material properties, silicon carbide recently emerged as a promising candidate for the scalable implementation of advanced quantum information processing capabilities. To date, however, only entanglement of nuclear spins has been reported in silicon carbide, while an entangled photon source, whether it is based on bulk or chip-scale technologies, has remained elusive. Here, we report the demonstration of an entangled photon source in an integrated silicon carbide platform for the first time. Specifically, strongly correlated photon pairs are efficiently generated at the telecom C-band wavelength through implementing spontaneous four-wave mixing in a compact microring resonator in the 4H-silicon-carbide-on-insulator platform. The maximum coincidence-to-accidental ratio exceeds 600 at a pump power of 0.17 mW, corresponding to a pair generation rate of (9 ± 1) × 103pairs/s. Energy-time entanglement is created and verified for such signal-idler photon pairs, with the two-photon interference fringes exhibiting a visibility larger than 99%. The heralded single-photon properties are also measured, with the heraldedg(2)(0) on the order of 10−3, demonstrating the SiC platform as a prospective fully integrated, complementary metal-oxide-semiconductor compatible single-photon source for quantum applications.
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Progress towards a widely usable integrated silicon photonic photon-pair source
Photon-pair generation at telecommunication wavelengths using high-quality silicon microring resonators is an active area of research. Here, we report on significant progress towards the ultimate goal of an integrated silicon microchip for bright generation of photon pairs with multiple stages of tunable optical filtering on the same chip. A high pair generation brightness of 6.5×1010pairs/s/mW2/nm is achieved. The resonance of the high-Q silicon microring resonator can be monitored using a high dynamic range readout of a photocurrent in an all-silicon p-i-n diode fabricated across the waveguide cross-section, which is used to align the ring resonance to the passbands or stopbands of the filters.
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- Award ID(s):
- 1640968
- PAR ID:
- 10156651
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- OSA Continuum
- Volume:
- 3
- Issue:
- 6
- ISSN:
- 2578-7519
- Format(s):
- Medium: X Size: Article No. 1398
- Size(s):
- Article No. 1398
- Sponsoring Org:
- National Science Foundation
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