Constant Overhead Entanglement Distillation via Scrambling.

Area of Science:

• Quantum Information Science
• Quantum Networking
• Quantum Computing

Background:

• High-fidelity quantum entanglement is crucial for quantum networking applications like secure communication and distributed quantum computing.
• Long-distance distribution of entanglement is hindered by noise and signal loss.
• Entanglement distillation protocols aim to improve entanglement quality but often require significant resources and complex operations.

Purpose of the Study:

• To introduce a novel entanglement distillation protocol that minimizes resource overhead.
• To overcome the practical implementation challenges of existing theoretical protocols.
• To enable efficient distribution of high-fidelity entangled pairs for quantum networks.

Main Methods:

• Utilized quantum scrambling, the spreading of quantum information via chaotic dynamics, through random Clifford operations.
• Developed protocols with asymptotically constant overhead, independent of the target output error rate.
• Implemented protocols using shallow quantum circuits and limited memory, suitable for practical applications.

Main Results:

• Achieved constant resource overhead, simplifying practical implementation.
• Demonstrated effectiveness even with noisy quantum gates.
• With error correction, distilled a Bell pair with 10^-12 infidelity from inputs with 10% infidelity using only seven noisy pairs.

Conclusions:

• The proposed quantum scrambling-based distillation protocol offers a practical and efficient solution for generating high-fidelity entanglement.
• The protocol achieves state-of-the-art performance, significantly outperforming existing schemes.
• Demonstrated the utility and effectiveness of the protocol for advancing quantum repeater networks.