Heralded Three-Photon Entanglement from a Single-Photon Source on a Photonic Chip

Area of Science:

• Quantum Information Science
• Quantum Optics
• Photonic Quantum Computing

Background:

• Fusion-based quantum computation offers a scalable pathway to universal quantum computing.
• Generating essential multi-photon entangled resource states on photonic chips remains a significant challenge.
• The heralded three-photon Greenberger-Horne-Zeilinger (3-GHZ) state is a critical, yet unachieved, resource for this architecture.

Purpose of the Study:

• To experimentally realize the heralded three-photon Greenberger-Horne-Zeilinger (3-GHZ) state for the first time.
• To address the resource gap hindering fusion-based photonic quantum computation.
• To demonstrate the feasibility of generating key entangled states on photonic chips.

Main Methods:

• Utilized a low-loss, fully programmable photonic chip.
• Employed the manipulation of six indistinguishable single photons in the telecommunication wavelength regime.
• Implemented a heralding detection mechanism to confirm the generation of the 3-GHZ state.

Main Results:

• Achieved the first experimental realization of a heralded 3-GHZ state.
• Obtained the desired 3-GHZ state with a fidelity of 0.573±0.024 upon heralding detection.
• Demonstrated the successful generation of a critical resource for quantum computing.

Conclusions:

• This work successfully bridges a fundamental resource gap in fusion-based quantum computation.
• The experimental realization of the heralded 3-GHZ state is a significant step towards fault-tolerant photonic quantum computing.
• This achievement accelerates the development of large-scale optical quantum computers.