In and out of equilibrium quantum metrology with mean-field quantum criticality

• URL: http://arxiv.org/abs/2001.03189v2
• Date: Sun, 10 May 2020 22:36:32 GMT
• Title: In and out of equilibrium quantum metrology with mean-field quantum criticality
• Authors: Sascha Wald, Saulo V. Moreira and Fernando L. Semi\~ao
• Abstract summary: We study the influence that collective transition phenomena have on quantum metrological protocols. The single spherical quantum spin (SQS) serves as stereotypical toy model that allows analytical insights on a mean-field level.
• Score: 68.8204255655161
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We study the influence that collective transition phenomena have on quantum metrological protocols. The single spherical quantum spin (SQS) serves as stereotypical toy model that allows analytical insights on a mean-field level. First, we focus on equilibrium quantum criticality in the SQS and obtain the quantum Fisher information analytically, which is associated with the minimum lower bound for the precision of estimation of the parameter driving the phase transition. We compare it with the Fisher information for a specific experimental scenario where photoncounting-like measurements are employed. We find how quantum criticality and squeezing are useful resources in the metrological scenario. Second, we obtain the quantum Fisher information for the out of equilibrium transition in the dissipative non-equilibrium steady state (NESS), and investigate how the presence of dissipation affects the parameter estimation. In this scenario, it is known that the critical point is shifted by an amount which depends on the dissipation rate. This is used here to design high precision protocols for a whole range of the transition-driving parameter in the ordered phase. In fact, for certain values of the parameter being estimated, dissipation may be used to obtain higher precision when compared to the equilibrium scenario.

Related papers

• Quantum sensing in Kerr parametric oscillators [0.0]
  Changes in the ground state at a QPT enhance indicators of parameter estimation. In systems that lack a QPT, quantum sensitivity can still be enhanced due to excited-state quantum phase transitions.
  arXiv  Detail & Related papers  (2024-07-19T18:00:00Z)
• Combining critical and quantum metrology [0.0]
  We introduce an approach combining two methodologies into a unified protocol applicable to closed and driven-dissipative systems. We provide analytical expressions for the quantum and classical Fisher information in such a setup, elucidating as well a straightforward measurement approach. We showcase these results by focusing on the squeezing Hamiltonian, which characterizes the thermodynamic limit of Dicke and Lipkin-Meshkov-Glick Hamiltonians.
  arXiv  Detail & Related papers  (2023-11-28T04:21:39Z)
• Universality of critical dynamics with finite entanglement [68.8204255655161]
  We study how low-energy dynamics of quantum systems near criticality are modified by finite entanglement. Our result establishes the precise role played by entanglement in time-dependent critical phenomena.
  arXiv  Detail & Related papers  (2023-01-23T19:23:54Z)
• Relative Phase Distribution and the Precision of Optical Phase Sensing in Quantum Metrology [0.0]
  We obtain the relative phase distribution introduced by Luis and S'anchez-Soto (LSS) for several two-mode pure quantum light states useful in quantum metrology. Our results indicate that the LSS relative phase distribution can be used to predict the minimum uncertainty possible in the process of phase sensing in quantum metrology.
  arXiv  Detail & Related papers  (2022-08-24T13:12:35Z)
• Experimental validation of the Kibble-Zurek Mechanism on a Digital Quantum Computer [62.997667081978825]
  The Kibble-Zurek mechanism captures the essential physics of nonequilibrium quantum phase transitions with symmetry breaking. We experimentally tested the KZM for the simplest quantum case, a single qubit under the Landau-Zener evolution. We report on extensive IBM-Q experiments on individual qubits embedded in different circuit environments and topologies.
  arXiv  Detail & Related papers  (2022-08-01T18:00:02Z)
• Probing finite-temperature observables in quantum simulators of spin systems with short-time dynamics [62.997667081978825]
  We show how finite-temperature observables can be obtained with an algorithm motivated from the Jarzynski equality. We show that a finite temperature phase transition in the long-range transverse field Ising model can be characterized in trapped ion quantum simulators.
  arXiv  Detail & Related papers  (2022-06-03T18:00:02Z)
• Enhanced nonlinear quantum metrology with weakly coupled solitons and particle losses [58.720142291102135]
  We offer an interferometric procedure for phase parameters estimation at the Heisenberg (up to 1/N) and super-Heisenberg scaling levels. The heart of our setup is the novel soliton Josephson Junction (SJJ) system providing the formation of the quantum probe. We illustrate that such states are close to the optimal ones even with moderate losses.
  arXiv  Detail & Related papers  (2021-08-07T09:29:23Z)
• QMetrology from QCosmology: Study with Entangled Two Qubit Open Quantum System in De Sitter Space [1.7549208519206603]
  We investigate the role of certain physical quantities in the open quantum dynamics of a two entangled qubit system under the Markovian approximation. We apply both Classical Fisher Information (CFI) and Quantum Fisher Information (QFI) to correctly estimate these parameters. We also present an interesting result of revival of out-of-equilibrium feature at the late time scales, arising due to the long range quantum entanglement at early time scale.
  arXiv  Detail & Related papers  (2020-05-27T18:00:04Z)
• Quantum Fisher information measurement and verification of the quantum Cram\'er-Rao bound in a solid-state qubit [11.87072483257275]
  We experimentally demonstrate near saturation of the quantum Cram'er-Rao bound in the phase estimation of a solid-state spin system. This is achieved by comparing the experimental uncertainty in phase estimation with an independent measurement of the related quantum Fisher information.
  arXiv  Detail & Related papers  (2020-03-18T17:51:06Z)
• Quantum Statistical Complexity Measure as a Signalling of Correlation Transitions [55.41644538483948]
  We introduce a quantum version for the statistical complexity measure, in the context of quantum information theory, and use it as a signalling function of quantum order-disorder transitions. We apply our measure to two exactly solvable Hamiltonian models, namely: the $1D$-Quantum Ising Model and the Heisenberg XXZ spin-$1/2$ chain. We also compute this measure for one-qubit and two-qubit reduced states for the considered models, and analyse its behaviour across its quantum phase transitions for finite system sizes as well as in the thermodynamic limit by using Bethe ansatz.
  arXiv  Detail & Related papers  (2020-02-05T00:45:21Z)

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.