Telecom-heralded entanglement between multimode solid-state quantum memories

Area of Science:

• Quantum Information Science
• Quantum Communication
• Solid-State Quantum Systems

Background:

• Future quantum networks require entanglement distribution between remote nodes for applications in communication, sensing, and computation.
• Existing entanglement methods lack compatibility with telecommunication wavelengths and multimode operation essential for network functionality.

Purpose of the Study:

• To demonstrate heralded entanglement between spatially separated quantum nodes using solid-state quantum memories.
• To achieve entanglement storage compatible with telecommunication wavelengths and capable of multimode operation.

Main Methods:

• Utilized praseodymium-doped crystals at each quantum node to store photons from correlated pairs.
• Heralded entanglement by detecting telecom-wavelength photons, achieving rates up to 1.4 kHz.
• Demonstrated entanglement storage for up to 25 microseconds and temporally multiplexed operation with 62 modes.

Main Results:

• Successfully generated heralded entanglement between two quantum memories in separate laboratories.
• Entanglement storage demonstrated robustness against loss in the heralding channel.
• Achieved temporally multiplexed operation, showcasing the potential for high-capacity quantum repeaters.

Conclusions:

• The developed system provides a viable route towards field-deployed, multiplexed quantum repeaters based on solid-state resources.
• This work is extendable to entanglement distribution over longer distances, crucial for scaling quantum networks.