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arXiv · 2507.12319

Single excitation swap in a modified Jaynes-Cummings-Hubbard lattice

Maritza Ahumada·Natalia Valderrama-Quinteros·Diego Tancara·Guillermo Romero
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Abstract

Controlling the transport and nature of quantum excitations in low-dimensional systems is a key requirement for scalable quantum devices, including communication networks and quantum simulators. We propose a one-dimensional hybrid quantum lattice model, in which each lattice unit integrates a single-mode resonator that interacts with a two-level system (TLS), featuring direct coupling between adjacent TLSs. This configuration enables the coherent propagation of excitations with tunable atomic, photonic, or polaritonic character. Beyond conventional single-excitation transport, we demonstrate that appropriate impedance-matching and resonance conditions allow for the controlled swapping of excitation type as the excitation propagates along the lattice. We analyze the resulting dynamics using local observables and pairwise concurrence to track both transport and quantum correlations. Our results establish a minimal platform for controlled single-excitation conversion, with direct relevance to hybrid quantum networks, on-chip quantum interconnects, and engineered quantum simulators.

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Maritza Ahumada, Natalia Valderrama-Quinteros, Diego Tancara, Guillermo Romero. 2025-07-16. Single excitation swap in a modified Jaynes-Cummings-Hubbard lattice. https://doi.org/10.1103/zzvj-jmyb

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