Activation of metrologically useful genuine multipartite entanglement

• URL: http://arxiv.org/abs/2203.05538v5
• Date: Thu, 7 Mar 2024 14:03:47 GMT
• Title: Activation of metrologically useful genuine multipartite entanglement
• Authors: R\'obert Tr\'enyi, \'Arp\'ad Luk\'acs, Pawe{\l} Horodecki, Ryszard Horodecki, Tam\'as V\'ertesi, G\'eza T\'oth
• Abstract summary: We consider quantum metrology with several copies of bipartite and multipartite quantum states. We identify a large class of entangled states that become maximally useful for metrology in the limit of large number of copies.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: We consider quantum metrology with several copies of bipartite and multipartite quantum states. We characterize the metrological usefulness by determining how much the state outperforms separable states. We identify a large class of entangled states that become maximally useful for metrology in the limit of large number of copies, even if the state is weakly entangled and not even more useful than separable states. This way we activate metrologically useful genuine multipartite entanglement. Remarkably, not only that the maximally achievable metrological usefulness is attained exponentially fast in the number of copies, but it can be achieved by the measurement of few simple correlation observables. We also make general statements about the usefulness of a single copy of pure entangled states. We surprisingly find that the multiqubit states presented in Hyllus et al. [Phys. Rev. A 82, 012337 (2010)], which are not useful, become useful if we embed the qubits locally in qutrits. We discuss the relation of our scheme to error correction, and its possible use for quantum metrology in a noisy environment.

Related papers

• Exponential Separations between Quantum Learning with and without Purification [0.7908933308312488]
  In quantum learning tasks, quantum memory can offer exponential reductions in statistical complexity compared to any single-copy strategies. We show that such exponential reductions can also be achieved by having access to the purification of the target mixed state.
  arXiv  Detail & Related papers  (2024-10-23T09:47:43Z)
• Optimal Local Measurements in Many-body Quantum Metrology [3.245777276920855]
  We propose a method dubbed as the "iterative matrix partition" approach to elucidate the underlying structures of optimal local measurements. We find that exact saturation is possible for all two-qubit pure states, but it is generically restrictive for multi-qubit pure states. We demonstrate that the qCRB can be universally saturated in an approximate manner through adaptive coherent controls.
  arXiv  Detail & Related papers  (2023-09-30T07:34:31Z)
• Sparse random Hamiltonians are quantumly easy [105.6788971265845]
  A candidate application for quantum computers is to simulate the low-temperature properties of quantum systems. This paper shows that, for most random Hamiltonians, the maximally mixed state is a sufficiently good trial state. Phase estimation efficiently prepares states with energy arbitrarily close to the ground energy.
  arXiv  Detail & Related papers  (2023-02-07T10:57:36Z)
• The power of noisy quantum states and the advantage of resource dilution [62.997667081978825]
  Entanglement distillation allows to convert noisy quantum states into singlets. We show that entanglement dilution can increase the resilience of shared quantum states to local noise.
  arXiv  Detail & Related papers  (2022-10-25T17:39:29Z)
• Quantum state tomography with tensor train cross approximation [84.59270977313619]
  We show that full quantum state tomography can be performed for such a state with a minimal number of measurement settings. Our method requires exponentially fewer state copies than the best known tomography method for unstructured states and local measurements.
  arXiv  Detail & Related papers  (2022-07-13T17:56:28Z)
• Learning quantum many-body systems from a few copies [1.5229257192293197]
  Estimating physical properties of quantum states from measurements is one of the most fundamental tasks in quantum science. We identify conditions on states under which it is possible to infer the expectation values of all quasi-local observables of a state. We show that this constitutes a provable exponential improvement in the number of copies over state-of-the-art tomography protocols.
  arXiv  Detail & Related papers  (2021-07-07T16:21:51Z)
• Heterogeneous Multipartite Entanglement Purification for Size-Constrained Quantum Devices [68.8204255655161]
  Purifying entanglement resources after their imperfect generation is an indispensable step towards using them in quantum architectures. Here we depart from the typical purification paradigm for multipartite states explored in the last twenty years. We find that smaller sacrificial' states, like Bell pairs, can be more useful in the purification of multipartite states than additional copies of these same states.
  arXiv  Detail & Related papers  (2020-11-23T19:00:00Z)
• New Genuine Multipartite Entanglement [0.0]
  We present a new kind of genuine multipartite entanglement. Results suggest that the present model is useful characterizing a new kind of generic quantum entanglement.
  arXiv  Detail & Related papers  (2020-03-16T12:44:42Z)
• Gaussian Process States: A data-driven representation of quantum many-body physics [59.7232780552418]
  We present a novel, non-parametric form for compactly representing entangled many-body quantum states. The state is found to be highly compact, systematically improvable and efficient to sample. It is also proven to be a universal approximator' for quantum states, able to capture any entangled many-body state with increasing data set size.
  arXiv  Detail & Related papers  (2020-02-27T15:54:44Z)
• Genuine Network Multipartite Entanglement [62.997667081978825]
  We argue that a source capable of distributing bipartite entanglement can, by itself, generate genuine $k$-partite entangled states for any $k$. We provide analytic and numerical witnesses of genuine network entanglement, and we reinterpret many past quantum experiments as demonstrations of this feature.
  arXiv  Detail & Related papers  (2020-02-07T13:26:00Z)
• Quantum states with a positive partial transpose are useful for metrology [0.0]
  We show that multipartite quantum states that have a positive partial transpose can outperform separable states in linear interferometers. We introduce a powerful iterative method to find such states. We find that quantum states that do not violate any Bell inequality can outperform separable states metrologically.
  arXiv  Detail & Related papers  (2017-09-12T18:00:46Z)

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.