Entanglement Sudden Death in Gapped Ground States
Abstract
Spatial sudden death of entanglement refers to the disappearance of quantum correlations between subsystems after a certain distance called the entanglement length. Specifically, given a density matrix ρABC on a tripartite system ABC with B spatially separating A and C, the entanglement length is the distance ℓ(A,C) after which the reduced density matrix ρAC, given by tracing out the B subsystem, is separable. We show in the case of gapped ground states in any dimension that the entanglement length is finite on finite subsystems. Restricting to one-dimensional systems, we prove that normal matrix product states have a finite entanglement length independent of A and C, and that a finite pure state with such uniform entanglement length has a matrix product state representation with bond dimension independent of A and C. Consequently, in one dimension, entanglement length distinguishes matrix product states from all other pure states.
Related
- Local determination of low-energy states in gapped fermion systems with weak long-range interactions
- Sharp universal death of entanglement threshold for Pauli Hamiltonians
- Serrin-type overdetermination in scaling limits: Sharp existence and asymptotic behavior of quasi-linear Schrödinger energy ground states
- Uniqueness, Nondegeneracy, and Asymptotic Expansions of Ground States for the Dirac-Coulomb System
- Ground States of Nonlinear Fermionic Systems: From Power-Law Interactions to Logarithmic Sobolev Inequality
BibTeX
@misc{ferydouni2026entanglement,
title = {{Entanglement Sudden Death in Gapped Ground States}},
author = {Robert Ferydouni and Thomas Jackson and Samuel O. Scalet},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.17038},
eprint = {2610.17038},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.17038},
}
RIS
TY - UNPB
TI - Entanglement Sudden Death in Gapped Ground States
AU - Robert Ferydouni
AU - Thomas Jackson
AU - Samuel O. Scalet
PY - 2026
DA - 2026/10/12
PB - arXiv
DO - 10.48550/arxiv.2610.17038
UR - https://arxiv.org/abs/2610.17038
AB - Spatial sudden death of entanglement refers to the disappearance of quantum correlations between subsystems after a certain distance called the entanglement length. Specifically, given a density matrix ρ_ABC on a tripartite system ABC with B spatially separating A and C, the entanglement length is the distance ℓ(A,C) after which the reduced density matrix ρ_AC, given by tracing out the B subsystem, is separable. We show in the case of gapped ground states in any dimension that the entanglement length is finite on finite subsystems. Restricting to one-dimensional systems, we prove that normal matrix product states have a finite entanglement length independent of A and C, and that a finite pure state with such uniform entanglement length has a matrix product state representation with bond dimension independent of A and C. Consequently, in one dimension, entanglement length distinguishes matrix product states from all other pure states.
ER -