Characterizing entanglement dynamics in QED scattering processes
- URL: http://arxiv.org/abs/2604.10136v1
- Date: Sat, 11 Apr 2026 10:04:44 GMT
- Title: Characterizing entanglement dynamics in QED scattering processes
- Abstract summary: We study entanglement dynamics among helicity degrees of freedom in quantum electrodynamics (QED) scattering processes.<n>For scattering involving fermions only, maximal entanglement present in the initial state is always preserved.<n>The structure of the maps also accounts for the entanglement dynamics in processes involving both fermions and photons.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We study entanglement dynamics among helicity degrees of freedom in quantum electrodynamics (QED) scattering processes. For generic initial states, we consider scattering at fixed momentum, corresponding to a generalized measurement described by a positive operator-valued measure, resulting in a post-measurement state. Such processes are modeled in terms of quantum maps, whose spectral structure fully determines the associated entanglement dynamics. For scattering involving fermions only, maximal entanglement present in the initial state is always preserved. Moreover, iterating the corresponding quantum maps on arbitrary initial states, we obtain the fixed points of the maps, which, in the largest number of cases, are asymptotic (pure) maximally entangled states. The structure of the maps also accounts for the entanglement dynamics in processes involving both fermions and photons. The defining properties of these maps originate from discrete symmetries of the QED interaction.
Related papers
- Direct derivation of the modified Langevin noise formalism from the canonical quantization of macroscopic electromagnetism [51.56484100374058]
We derive the exact analytical expressions for the polariton operators in terms of the canonical CQME field operators.<n>We provide a direct and rigorous derivation of the Langevin noise formalism from the canonical theory in the Schrdinger picture.
arXiv Detail & Related papers (2026-03-04T17:53:31Z) - Grassmann Variational Monte Carlo with neural wave functions [45.935798913942904]
We formalize the framework introduced by Pfau et al.citepfau2024accurate in terms of Grassmann geometry of the Hilbert space.<n>We validate our approach on the Heisenberg quantum spin model on the square lattice, achieving highly accurate energies and physical observables for a large number of excited states.
arXiv Detail & Related papers (2025-07-14T13:53:13Z) - Entanglement saturation in quantum electrodynamics scattering processes [0.0]
We investigate the properties of two-particle scattering processes when an arbitrarily sharp filtering of the outgoing particles in momentum space is performed.<n>We find that these processes are described by dynamical quantum maps, whose structure is such that any initial state is transformed into a maximally entangled state, after an infinite number of iterations of the map.<n>This structural property is exactly realized if all the colliding particles are massive fermions while, when photons are involved, it is verified in a partial way, depending on the process under consideration.
arXiv Detail & Related papers (2025-05-11T07:09:54Z) - Symmetries, Conservation Laws and Entanglement in Non-Hermitian Fermionic Lattices [37.69303106863453]
Non-Hermitian quantum many-body systems feature steady-state entanglement transitions driven by unitary dynamics and dissipation.<n>We show that the steady state is obtained by filling single-particle right eigenstates with the largest imaginary part of the eigenvalue.<n>We illustrate these principles in the Hatano-Nelson model with periodic boundary conditions and the non-Hermitian Su-Schrieffer-Heeger model.
arXiv Detail & Related papers (2025-04-11T14:06:05Z) - Exploring entanglement in finite-size quantum systems with degenerate ground state [0.0]
We develop an approach for characterizing non-local quantum correlations in spin systems with exactly or nearly degenerate ground states.<n> Estimating the von Neumann entropy of the random wave functions helps to reveal previously unknown features of the quantum correlations in the phases with degeneracy of the ground state.<n>Digital quantum simulations performed with quantum computers can provide accurate description of the entanglement of the degenerate systems even in the presence of noise.
arXiv Detail & Related papers (2024-10-01T08:56:34Z) - Quantum electrodynamics of lossy magnetodielectric samples in vacuum: modified Langevin noise formalism [55.2480439325792]
We analytically derive the modified Langevin noise formalism from the established canonical quantization of the electromagnetic field in macroscopic media.
We prove that each of the two field parts can be expressed in term of particular bosonic operators, which in turn diagonalize the electromagnetic Hamiltonian.
arXiv Detail & Related papers (2024-04-07T14:37:04Z) - Quantum tomography of helicity states for general scattering processes [55.2480439325792]
Quantum tomography has become an indispensable tool in order to compute the density matrix $rho$ of quantum systems in Physics.
We present the theoretical framework for reconstructing the helicity quantum initial state of a general scattering process.
arXiv Detail & Related papers (2023-10-16T21:23:42Z) - Meson content of entanglement spectra after integrable and nonintegrable
quantum quenches [0.0]
We calculate the time evolution of the lower part of the entanglement spectrum and return rate functions after global quantum quenches in the Ising model.
Our analyses provide a deeper understanding on the role of quantum information quantities for the dynamics of emergent phenomena reminiscent to systems in high-energy physics.
arXiv Detail & Related papers (2022-10-27T18:00:01Z) - A tutorial introduction to quantum stochastic master equations based on
the qubit/photon system [0.0]
This article explains the Kraus-map structure of general discrete-time SME governing the dynamics of an open quantum system.
Simple linear integration schemes are derived that preserve the positivity and the trace of the density operator.
arXiv Detail & Related papers (2022-08-15T19:38:39Z) - Correlated steady states and Raman lasing in continuously pumped and
probed atomic ensembles [68.8204255655161]
We consider an ensemble of Alkali atoms that are continuously optically pumped and probed.
Due to the collective scattering of photons at large optical depth, the steady state of atoms does not correspond to an uncorrelated tensor-product state.
We find and characterize regimes of Raman lasing, akin to the model of a superradiant laser.
arXiv Detail & Related papers (2022-05-10T06:54:54Z) - Quantum particle across Grushin singularity [77.34726150561087]
We study the phenomenon of transmission across the singularity that separates the two half-cylinders.
All the local realisations of the free (Laplace-Beltrami) quantum Hamiltonian are examined as non-equivalent protocols of transmission/reflection.
This allows to comprehend the distinguished status of the so-called bridging' transmission protocol previously identified in the literature.
arXiv Detail & Related papers (2020-11-27T12:53:23Z) - Unraveling the topology of dissipative quantum systems [58.720142291102135]
We discuss topology in dissipative quantum systems from the perspective of quantum trajectories.
We show for a broad family of translation-invariant collapse models that the set of dark state-inducing Hamiltonians imposes a nontrivial topological structure on the space of Hamiltonians.
arXiv Detail & Related papers (2020-07-12T11:26:02Z)
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.