A theoretical treatment of optical metasurfaces as an efficient basis for quantum correlations

TL;DR

This paper explores how optical metasurfaces can be used as compact, tunable platforms for generating and maintaining high-fidelity quantum entanglement, specifically Bell states, through a Hamiltonian-driven mechanism.

Contribution

It introduces a theoretical framework demonstrating metasurfaces as effective tools for quantum entanglement generation and analyzes their robustness against decoherence.

Findings

Metasurfaces can produce Bell states with concurrence ~0.995.

Quantum discord persists for up to 29 microseconds.

System evolution under a metasurface Hamiltonian achieves maximal entanglement.

Abstract

Entanglement is a cornerstone of quantum technology, playing a key role in quantum computing, cryptography, and information processing. Conventional methods for generating entanglement via optical setups rely on beam splitters, nonlinear media, or quantum dots, which often require bulky configurations and precise phase control. In contrast, metasurfaces - ultrathin, engineered optical interfaces - offer a compact and tunable alternative for quantum photonics. In this work, we demonstrate that metasurfaces can serve as a promising platform for generating Bell states through a Hamiltonian-driven spin-entanglement mechanism. By analyzing the system's evolution under a metasurface interaction Hamiltonian, we show that an initially separable spin state evolves into a maximally entangled Bell state. We further study classical and quantum correlations, evaluate the impact of environmental decoherence, and compute quantum discord to quantify correlation robustness beyond entanglement. Our analysis shows that metasurfaces can generate Bell states with a concurrence of about 0.995 and maintain quantum discord for up to 29 microseconds. These results establish metasurfaces as scalable, high-fidelity components for next-generation quantum photonic architectures.