Entanglement negativity for a free scalar chiral current

• URL: http://arxiv.org/abs/2601.04995v1
• Date: Thu, 08 Jan 2026 14:52:50 GMT
• Title: Entanglement negativity for a free scalar chiral current
• Authors: Malen Arias, Marina Huerta, Andrei Rotaru, Erik Tonni,
• Abstract summary: We study the entanglement negativity for the free, scalar chiral current in two spacetime dimensions.<n>We find analytic expressions for the moments of the partial transpose of the reduced density matrix and the logarithmic negativity.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We study the entanglement negativity for the free, scalar chiral current in two spacetime dimensions, which is a simple model violating the Haag duality in regions with nontrivial topology. For the ground state of the system, both on the line and on the circle, we consider the setups given by two intervals, either adjacent or disjoint. We find analytic expressions for the moments of the partial transpose of the reduced density matrix and the logarithmic negativity. In the limit of small separation distance, this expression yields the same subleading topological contribution occurring in the mutual information. In the limit of large separation distance between the two intervals, the exponential decay of the logarithmic negativity is obtained from its analytic expression. The analytic formulas are checked against exact numerical results from a bosonic lattice model, finding a perfect agreement. We observe that, since the chiral current generates the neutral subalgebra of the full chiral Dirac fermion theory, this analysis highlights how symmetries produce nontrivial features in the entanglement structure that are analogue to those ones already observed in the mutual information for regions with nontrivial topology.

Related papers

• Symmetry-protected topology and deconfined solitons in a multi-link $\mathbb{Z}_2$ gauge theory [45.88028371034407]
  We study a $mathbbZ$ lattice gauge theory defined on a multi-graph with links that can be visualized as great circles of a spherical shell.<n>We show that this leads to state-dependent tunneling amplitudes underlying a phenomenon analogous to the Peierls instability.<n>By performining a detailed analysis based on matrix product states, we prove that charge deconfinement emerges as a consequence of charge-fractionalization.
  arXiv  Detail & Related papers  (2026-03-02T22:59:25Z)
• A contour for the entanglement negativity of bosonic Gaussian states [0.0]
  In one spatial dimension, numerical results are obtained for harmonic chains either in the ground state or at finite temperature.<n>We report numerical results showing that this quantity displays a monotonically decreasing behaviour.
  arXiv  Detail & Related papers  (2026-02-20T09:40:37Z)
• Parametric resonant enhancement of motional entanglement under optimal control: an analytical study [45.88028371034407]
  We study theoretically continuous-variable entanglement between the motional degrees of freedom of optically trapped massive particles coupled via the Coulomb interaction.<n>We perform a detailed analysis of the parametric resonance induced by temporal modulation of the coupling strength, based on the system's coupled nonlinear, nonhomogeneous dynamical equations.<n>We demonstrate that a stationary nonequilibrium entangled state is realized as a result of the competition between parametric gain and decoherence.
  arXiv  Detail & Related papers  (2025-10-21T09:01:19Z)
• Sampling and estimation on manifolds using the Langevin diffusion [45.57801520690309]
  Two estimators of linear functionals of $mu_phi $ based on the discretized Markov process are considered.<n>Error bounds are derived for sampling and estimation using a discretization of an intrinsically defined Langevin diffusion.
  arXiv  Detail & Related papers  (2023-12-22T18:01:11Z)
• Symmetry resolution of the computable cross-norm negativity of two disjoint intervals in the massless Dirac field theory [0.8309949345495992]
  entanglement in the mixed state of a quantum field theory can be described using the cross-computable norm or realignment criterion. We study its symmetry resolution for two disjoint intervals in the ground state of the massless Dirac fermion field theory. We show that, for two disjoint intervals, they correspond to the partition function of the theory on a torus with a non-contractible charged loop.
  arXiv  Detail & Related papers  (2023-12-05T17:56:48Z)
• Entanglement negativity between separated regions in quantum critical systems [0.0]
  We study the entanglement between disjoint subregions in quantum critical systems through the lens of the logarithmic negativity. At small separations, the logarithmic negativity is big and displays universal behavior, but we show non-perturbatively that it decays faster than any power at large separations. The corresponding absence of distillable entanglement at large separations generalizes the 1d result, and indicates that quantum critical groundstates do not possess long-range bipartite entanglement, at least for bosons.
  arXiv  Detail & Related papers  (2023-10-23T18:20:29Z)
• Robust extended states in Anderson model on partially disordered random regular graphs [44.99833362998488]
  It is shown that the mobility edge in the spectrum survives in a certain range of parameters $(d,beta)$ at infinitely large uniformly distributed disorder. The duality in the localization properties between the sparse and extremely dense RRG has been found and understood.
  arXiv  Detail & Related papers  (2023-09-11T18:00:00Z)
• Logarithmic Negativity and Spectrum in Free Fermionic Systems for Well-separated Intervals [0.0]
  We find that none of the eigenvalues of the density matrix become negative, but rather they develop a small imaginary value, leading to non-zero logarithmic negativity. One may compute logarithmic negativity in further situations, but we find that the results are non-universal, depending non-smoothly on the Fermi level and the size of the intervals in units of the lattice spacing.
  arXiv  Detail & Related papers  (2023-05-26T12:05:32Z)
• Extensive Long-Range Entanglement in a Nonequilibrium Steady State [0.0]
  Entanglement measures constitute powerful tools in the quantitative description of quantum many-body systems out of equilibrium. We study entanglement in the current-carrying steady state of a paradigmatic one-dimensional model of noninteracting fermions at zero temperature in the presence of a scatterer.
  arXiv  Detail & Related papers  (2022-05-25T18:01:16Z)
• Locality of Spontaneous Symmetry Breaking and Universal Spacing Distribution of Topological Defects Formed Across a Phase Transition [62.997667081978825]
  A continuous phase transition results in the formation of topological defects with a density predicted by the Kibble-Zurek mechanism (KZM) We characterize the spatial distribution of point-like topological defects in the resulting nonequilibrium state and model it using a Poisson point process in arbitrary spatial dimension with KZM density.
  arXiv  Detail & Related papers  (2022-02-23T19:00:06Z)
• Spectrum of localized states in fermionic chains with defect and adiabatic charge pumping [68.8204255655161]
  We study the localized states of a generic quadratic fermionic chain with finite-range couplings. We analyze the robustness of the connection between bands against perturbations of the Hamiltonian.
  arXiv  Detail & Related papers  (2021-07-20T18:44:06Z)
• Long-distance entanglement of purification and reflected entropy in conformal field theory [58.84597116744021]
  We study entanglement properties of mixed states in quantum field theory via entanglement of purification and reflected entropy. We find an elementary proof that the decay of both, the entanglement of purification and reflected entropy, is enhanced with respect to the mutual information behaviour.
  arXiv  Detail & Related papers  (2021-01-29T19:00:03Z)
• Entanglement negativity spectrum of random mixed states: A diagrammatic approach [0.34410212782758054]
  entanglement properties of random pure states are relevant to a variety of problems ranging from chaotic quantum dynamics to black hole physics. In this paper, we generalize this setup to random mixed states by coupling the system to a bath and use the partial transpose to study their entanglement properties.
  arXiv  Detail & Related papers  (2020-11-02T19:49:37Z)
• Dynamical solitons and boson fractionalization in cold-atom topological insulators [110.83289076967895]
  We study the $mathbbZ$ Bose-Hubbard model at incommensurate densities. We show how defects in the $mathbbZ$ field can appear in the ground state, connecting different sectors. Using a pumping argument, we show that it survives also for finite interactions.
  arXiv  Detail & Related papers  (2020-03-24T17:31:34Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.