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arXiv · 2506.09561

Quench dynamics of negativity Hamiltonians

Riccardo Travaglino·Colin Rylands·Pasquale Calabrese
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Abstract

In this paper, we investigate the quench dynamics of the negativity and fermionic negativity Hamiltonians in free fermionic systems. We do this by generalizing a recently developed quasiparticle picture for the entanglement Hamiltonians to tripartite geometries. We obtain analytic expressions for these quantities which are then extensively checked against previous results and numerics. In particular, we find that the standard negativity Hamiltonian contains both non-local hopping terms and four fermion interactions, whereas the fermionic version is purely quadratic. However, despite their marked difference, we show that the logarithmic negativity obtained from either are identical in the ballistic scaling limit, as are their symmetry resolution.

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Riccardo Travaglino, Colin Rylands, Pasquale Calabrese. 2025-06-11. Quench dynamics of negativity Hamiltonians. https://doi.org/10.1088/1742-5468%2Fadfe58

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