Communications in Theoretical Physics

Qubit-qubit quantum coherence mediated by an epsilon-near-zero waveguide

Zhenhua Yin, Jicheng Wang, Yueke Wang, Yun Zhu, Mengmeng Li, Sergei A. Khakhomov, Zheng-Da Hu

Published Aug 26, 2024• 1 citation

Abstract

Abstract Quantum coherence, as a more general quantum resource compared to quantum entanglement, has attracted increasing attention over recent years. Establishing stable quantum coherence is crucial for implementing reliable quantum information tasks. In this study, we propose a scheme to generate stable quantum coherence of two qubits via an epsilon-near-zero (ENZ) waveguide. We find that employing Si3N4 rather than SiO2 results in stronger qubit-qubit coupling and maximal quantum coherence in a certain range. We derive analytical expressions for both quantum coherence and quantum entanglement, allowing for direct comparison within a unified framework. To achieve stable quantum coherence, classical field driving is introduced. We find that stable coherence is much larger and easier mediated than that of stable entanglement. Our work contributes to the creation of a new stable quantum resource via an ENZ waveguide.

DOI: 10.1088/1572-9494/ad7371

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