Symmetric Localizable Multipartite Quantum Measurements from Pauli Orbits

• URL: http://arxiv.org/abs/2509.01851v1
• Date: Tue, 02 Sep 2025 00:37:28 GMT
• Title: Symmetric Localizable Multipartite Quantum Measurements from Pauli Orbits
• Authors: Jef Pauwels, Cyril Branciard, Alejandro Pozas-Kerstjens, Nicolas Gisin,
• Abstract summary: We introduce a general approach to construct highly symmetric, locally encodable orthonormal measurement bases.<n>We show how the symmetry of our constructions allows us to characterize their localizability, which is generally a challenging problem.<n>Our approach offers a systematic toolkit for designing entangled measurements with rich symmetry and implementability properties.
• Score: 39.3098730337656
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: While the structure of entangled quantum states is relatively well understood, the characterization of entangled measurements, especially in multipartite and high-dimensional settings, remains far less developed. In this work, we introduce a general approach to construct highly symmetric, locally encodable orthonormal measurement bases, as orbits of a single fiducial state under tensor-product actions of Pauli subgroups. This framework recovers the Elegant Joint Measurement-a two-qubit measurement whose local marginals form a regular tetrahedron on the Bloch sphere-as a special case, and we extend the construction to both more systems and higher dimensions. We analyze the entanglement cost required to implement these measurements locally via the Clifford hierarchy and use this criterion to classify them. We show how the symmetry of our constructions allows us to characterize their localizability, which is generally a challenging problem, and to identify certain classes of measurement bases that are efficiently localizable. Our approach offers a systematic toolkit for designing entangled measurements with rich symmetry and implementability properties.

Related papers

• Enhancing entanglement asymmetry in fragmented quantum systems [0.10923877073891443]
  Entanglement asymmetry provides a measure of symmetry breaking in many-body quantum states.<n>We show that the typical asymmetry is bounded by a specific fraction of its maximal value.<n>We reproduce recent findings on the entanglement asymmetry dynamics in random quantum circuits.
  arXiv  Detail & Related papers  (2026-03-02T19:10:30Z)
• Riemannian Zeroth-Order Gradient Estimation with Structure-Preserving Metrics for Geodesically Incomplete Manifolds [57.179679246370114]
  We construct metrics that are geodesically complete while ensuring that every stationary point under the new metric remains stationary under the original one.<n>An $$-stationary point under the constructed metric $g'$ also corresponds to an $$-stationary point under the original metric $g'$.<n>Experiments on a practical mesh optimization task demonstrate that our framework maintains stable convergence even in the absence of geodesic completeness.
  arXiv  Detail & Related papers  (2026-01-12T22:08:03Z)
• Localizing entanglement in high-dimensional states [0.12314765641075437]
  We study protocols that localize entanglement in large multi-qubit states onto a subset of qubits by measuring the remaining qubits.<n>We use the maximal average n-tangle that can be generated on a fixed subsystem by measuring its complement as our key figure of merit.
  arXiv  Detail & Related papers  (2025-10-09T17:39:58Z)
• Generalised state space geometry in Hermitian and non-Hermitian quantum systems [0.0]
  We show that it is possible to construct a family of connections that are dual to each other in a generalised sense.<n>We also elucidate the role of the metric in a quantum natural gradient descent problem.
  arXiv  Detail & Related papers  (2025-07-24T15:01:04Z)
• Classification of joint quantum measurements based on entanglement cost of localization [42.72938925647165]
  We propose a systematic classification of joint measurements based on entanglement cost. We show how to numerically explore higher levels and construct generalizations to higher dimensions and multipartite settings.
  arXiv  Detail & Related papers  (2024-08-01T18:00:01Z)
• Finite-Depth Preparation of Tensor Network States from Measurement [0.0]
  We explore criteria on the local tensors for enabling deterministic state preparation via a single round of measurements. We use these criteria to construct families of measurement-preparable states in one and two dimensions. Our protocol even allows one to engineer preparable quantum states with a range of desired correlation lengths and entanglement properties.
  arXiv  Detail & Related papers  (2024-04-26T00:37:00Z)
• Enhanced Entanglement in the Measurement-Altered Quantum Ising Chain [43.80709028066351]
  Local quantum measurements do not simply disentangle degrees of freedom, but may actually strengthen the entanglement in the system.<n>This paper explores how a finite density of local measurement modifies a given state's entanglement structure.
  arXiv  Detail & Related papers  (2023-10-04T09:51:00Z)
• A Unifying and Canonical Description of Measure-Preserving Diffusions [60.59592461429012]
  A complete recipe of measure-preserving diffusions in Euclidean space was recently derived unifying several MCMC algorithms into a single framework. We develop a geometric theory that improves and generalises this construction to any manifold.
  arXiv  Detail & Related papers  (2021-05-06T17:36:55Z)
• Generalized quantum measurements with matrix product states: Entanglement phase transition and clusterization [58.720142291102135]
  We propose a method for studying the time evolution of many-body quantum lattice systems under continuous and site-resolved measurement. We observe a peculiar phenomenon of measurement-induced particle clusterization that takes place only for frequent moderately strong measurements, but not for strong infrequent measurements.
  arXiv  Detail & Related papers  (2021-04-21T10:36:57Z)
• Observing a Topological Transition in Weak-Measurement-Induced Geometric Phases [55.41644538483948]
  Weak measurements in particular, through their back-action on the system, may enable various levels of coherent control. We measure the geometric phases induced by sequences of weak measurements and demonstrate a topological transition in the geometric phase controlled by measurement strength. Our results open new horizons for measurement-enabled quantum control of many-body topological states.
  arXiv  Detail & Related papers  (2021-02-10T19:00:00Z)

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.