Optimal Local Measurements in Many-body Quantum Metrology

• URL: http://arxiv.org/abs/2310.00285v1
• Date: Sat, 30 Sep 2023 07:34:31 GMT
• Title: Optimal Local Measurements in Many-body Quantum Metrology
• Authors: Jia-Xuan Liu, Jing Yang, Hai-Long Shi, and Sixia Yu
• Abstract summary: 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.
• Score: 3.245777276920855
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Quantum measurements are key to quantum metrology. Constrained by experimental capabilities, collective measurements on a large number of copies of metrological probes can pose significant challenges. Therefore, the locality in quantum measurements must be considered. In this work, we propose a method dubbed as the "iterative matrix partition" approach to elucidate the underlying structures of optimal local measurements, with and without classical communications, that saturate the quantum Cram\'er-Rao Bound (qCRB). Furthermore, we find that while exact saturation is possible for all two-qubit pure states, it is generically restrictive for multi-qubit pure states. However, we demonstrate that the qCRB can be universally saturated in an approximate manner through adaptive coherent controls, as long as the initial state is separable and the Hamiltonian allows for interaction. Our results bridge the gap between theoretical proposals and experiments in many-body metrology and can find immediate applications in noisy intermediate-scale quantum devices.

Related papers

• Enhancing Quantum Metrology by Quantum Resonance Dynamics [0.6963971634605796]
  Quantum effects in metrology can enhance measurement precision from the so-called standard quantum limit to the Heisenberg Limit. In this Letter, we propose a protocol that can circumvent a number of known obstacles and still make good use of time. The proposed protocol can be tested on available experimental platforms.
  arXiv  Detail & Related papers  (2025-02-03T15:53:19Z)
• Optimal quantum state tomography with local informationally complete measurements [25.33379738135298]
  We study whether a general MPS/MPDO state can be recovered with bounded errors using only a number of state copies in the number of qubits. We provide a positive answer for a variety of common many-body quantum states, including typical short-range entangled states, random MPS/MPDO states, and thermal states of one-dimensional Hamiltonians.
  arXiv  Detail & Related papers  (2024-08-13T17:58:02Z)
• 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)
• Universal quantum frequency comb measurements by spectral mode-matching [39.58317527488534]
  We present the first general approach to make arbitrary, one-shot measurements of a multimode quantum optical source. This approach uses spectral mode-matching, which can be understood as interferometry with a memory effect.
  arXiv  Detail & Related papers  (2024-05-28T15:17:21Z)
• Realization of versatile and effective quantum metrology using a single bosonic mode [0.0]
  We present a versatile and on-demand protocol for deterministic parameter estimation. With low average photon numbers of only up to 1.76, we achieve quantum-enhanced precision approaching the Heisenberg scaling. We show that the gain or sensitivity range can be further enhanced on the fly by tailoring the input states.
  arXiv  Detail & Related papers  (2024-03-22T05:47:47Z)
• Quantum State Tomography for Matrix Product Density Operators [28.799576051288888]
  Reconstruction of quantum states from experimental measurements is crucial for the verification and benchmarking of quantum devices. Many physical quantum states, such as states generated by noisy, intermediate-scale quantum computers, are usually structured. We establish theoretical guarantees for the stable recovery of MPOs using tools from compressive sensing and the theory of empirical processes.
  arXiv  Detail & Related papers  (2023-06-15T18:23:55Z)
• Anticipative measurements in hybrid quantum-classical computation [68.8204255655161]
  We present an approach where the quantum computation is supplemented by a classical result. Taking advantage of its anticipation also leads to a new type of quantum measurements, which we call anticipative. In an anticipative quantum measurement the combination of the results from classical and quantum computations happens only in the end.
  arXiv  Detail & Related papers  (2022-09-12T15:47:44Z)
• Approaching optimal entangling collective measurements on quantum computing platforms [0.3665899982351484]
  We show theoretically optimal single- and two-copy collective measurements for simultaneously estimating two non-commuting qubit rotations. This allows us to implement quantum-enhanced sensing, for which the metrological gain persists for high levels of decoherence.
  arXiv  Detail & Related papers  (2022-05-30T18:07:27Z)
• Entanglement and Quantum Correlation Measures from a Minimum Distance Principle [0.0]
  Entanglement, and quantum correlation, are precious resources for quantum technologies implementation based on quantum information science. We derive an explicit measure able to quantify the degree of quantum correlation for pure or mixed multipartite states. We prove that our entanglement measure is textitfaithful in the sense that it vanishes only on the set of separable states.
  arXiv  Detail & Related papers  (2022-05-14T22:18:48Z)
• Entanglement catalysis for quantum states and noisy channels [41.94295877935867]
  We investigate properties of entanglement and its role for quantum communication. For transformations between bipartite pure states, we prove the existence of a universal catalyst. We further develop methods to estimate the number of singlets which can be established via a noisy quantum channel.
  arXiv  Detail & Related papers  (2022-02-10T18:36:25Z)
• Transmission Estimation at the Fundamental Quantum Cram\'er-Rao Bound with Macroscopic Quantum Light [0.0]
  We show that it is possible to perform measurements with the required precision to do so. For our largest transmission level of 84%, we show a 62% reduction over the optimal classical protocol in the variance in transmission estimation.
  arXiv  Detail & Related papers  (2022-01-21T21:50:24Z)

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.