High-Dimensional Two-Photon Quantum Controlled Phase-Flip Gate

TL;DR

This paper proposes a high-dimensional, deterministic, and universal two-photon quantum controlled phase-flip gate using an ion-cavity QED system, achieving high fidelity and enabling advanced quantum information processing.

Contribution

It introduces the first high-dimensional, deterministic, and universal two-photon quantum gate based on an ion-cavity system, with high fidelity in four-dimensional space.

Findings

Achieved over 98% fidelity for the gate

Demonstrated high success probability in high dimensions

Provided a platform for high-dimensional quantum information processing

Abstract

High-dimensional quantum systems have been used to reveal interesting fundamental physics and to improve information capacity and noise resilience in quantum information processing. However, it remains a significant challenge to realize universal two-photon quantum gates in high dimensions with high success probability. Here, by considering an ion-cavity QED system, we theoretically propose, to the best of our knowledge, the first high-dimensional, deterministic and universal two-photon quantum gate. By using an optical cavity embedded with a single trapped 40Ca+ ion, we achieve a high average fidelity larger than 98% for a quantum controlled phase-flip gate in four-dimensional space, spanned by photonic spin angular momenta and orbital angular momenta. Our proposed system can be an essential building block for high-dimensional quantum information processing, and also provides a platform for studying high-dimensional cavity QED.