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arXiv · 2504.18724

Micromagnons and long-range entanglement in ferrimagnetic ground states

Marcin Wieśniak·Ankit Kumar·Idriss Hank Nkouatchoua Ngueya
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Abstract

While significant attention has been devoted to studying entanglement in photonic systems, solid-state spin lattices remain relatively underexplored. Motivated by this gap, we investigate the entanglement structure of one-dimensional ferrimagnetic chains composed of alternating spin-1/2 and spin-3/2 particles. We characterize the ground-state correlations using exact diagonalization and the Density Matrix Renormalization Group method. Although the bipartite entanglement is restricted to nearest neighbors, we reveal the presence of long-range genuine multipartite entanglement between spatially separated spin pairs. These findings advance our understanding of quantum correlations in ferrimagnetic materials. The micromagnon description allows to provide fast approximation of ground states of ferrimagnets and emphasizes presence of multipartite correlations not widely discussed thus far.

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Marcin Wieśniak, Ankit Kumar, Idriss Hank Nkouatchoua Ngueya. 2025-04-25. Micromagnons and long-range entanglement in ferrimagnetic ground states. https://doi.org/10.1103/wwr6-l3dq

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