Related papers: The effect of non-selective measurement on the parameter estimation within spin-spin model

The effect of non-selective measurement on the parameter estimation within spin-spin model

URL: http://arxiv.org/abs/2409.09134v1
Date: Fri, 13 Sep 2024 18:21:33 GMT
Title: The effect of non-selective measurement on the parameter estimation within spin-spin model
Authors: Ali Raza Mirza, Jim Al-Khalili,
Abstract summary: We compare the estimation results obtained via projective measurement with the results obtained via unitary operation. In this paper, we study the estimation of bath temperature and probe-bath coupling strength which is quantified by the quantum Fisher information.
Score: 0.0
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: We investigate the role of non-selective measurement on the estimation of system-environment parameters. Projective measurement is the popular method of initial state preparation which always prepares a pure state. However, in various physical situations of physical interest, this selective measurement becomes unrealistic. In this paper, we compare the estimation results obtained via projective measurement with the results obtained via unitary operation. We argue that in typical situations, parameters can be estimated with higher accuracy if the initial state is prepared with the unitary operator (a pulse). We consider the spin-spin model where a central two-level system (probe) interacts with the collections of two-level systems (bath). A probe interacts with a bath and attains a thermal equilibrium state, then via unitary operation, the initial state is prepared which evolves unitarily. The properties of the bath are imprinted on the reduced dynamics. Due to the initial probe-bath correlations present in the thermal equilibrium state, an additional factor arises in the dynamics which has a phenomenal role in the parameter estimation. In this paper, we study the estimation of bath temperature and probe-bath coupling strength which is quantified by the quantum Fisher information. Our results are promising as one can improve the precision of the estimates by orders of magnitude via non-selective measurement and by incorporating the effect of initial correlations.

Related papers

The role of initial system-environment correlations in the accuracies of parameters within spin-spin model [0.0]
We investigate the effect of initial system-environment correlations to improve the estimation of environment parameters. In the temperature estimation case, our results are promising as one can improve the precision of the estimates by orders of magnitude. In the case of coupling strength, interestingly the accuracy was found to be continuously increasing in both with and without correlations cases.
arXiv Detail & Related papers (2024-07-04T02:25:51Z)
Toy model illustrating the effect of measurement dependence on a Bell inequality [0.0]
We show that the probabilities of adopting configurations of hidden variables describing a system prior to measurement are independent of the choice of physical property that will be measured. We demonstrate how this can emerge and illustrate the relaxed upper limit using a simple toy model of dynamical quantum measurement.
arXiv Detail & Related papers (2023-07-14T23:20:36Z)
Evolution of many-body systems under ancilla quantum measurements [58.720142291102135]
We study the concept of implementing quantum measurements by coupling a many-body lattice system to an ancillary degree of freedom. We find evidence of a disentangling-entangling measurement-induced transition as was previously observed in more abstract models.
arXiv Detail & Related papers (2023-03-13T13:06:40Z)
Measurement-altered Ising quantum criticality [6.436344983789632]
We show that measurements can alter long-distance correlations in a manner dependent on the choice of entangling gate, ancilla measurement basis, measurement outcome, and nature of ancilla correlations. We also identify two strategies for detecting measurement-altered Ising criticality in measurement-averaged quantities.
arXiv Detail & Related papers (2023-02-08T20:40:26Z)
Simulating spin measurement with a finite heat bath model for the environment [2.8360662552057323]
Spin measurement is studied as a unitary time evolution of the spin coupled to an environment representing the meter and the apparatus. We perform numerical simulations of projective measurements of the polarization, with the spins prepared initially in a neutral pure state. The expected quantum randomness in the final state is manifest in our simulations as a tendency of the spin to approach either one of the two eigenstates of the measured spin operator.
arXiv Detail & Related papers (2022-04-24T02:01:46Z)
Experimentally determining the incompatibility of two qubit measurements [55.41644538483948]
We describe and realize an experimental procedure for assessing the incompatibility of two qubit measurements. We demonstrate this fact in an optical setup, where the qubit states are encoded into the photons' polarization degrees of freedom.
arXiv Detail & Related papers (2021-12-15T19:01:44Z)
Finite resolution ancilla-assisted measurements of quantum work distributions [77.34726150561087]
We consider an ancilla-assisted protocol measuring the work done on a quantum system driven by a time-dependent Hamiltonian. We consider system Hamiltonians which both commute and do not commute at different times, finding corrections to fluctuation relations like the Jarzynski equality and the Crooks relation.
arXiv Detail & Related papers (2021-11-30T15:08:25Z)
Entropy Production and the Role of Correlations in Quantum Brownian Motion [77.34726150561087]
We perform a study on quantum entropy production, different kinds of correlations, and their interplay in the driven Caldeira-Leggett model of quantum Brownian motion.
arXiv Detail & Related papers (2021-08-05T13:11:05Z)
Leveraging Global Parameters for Flow-based Neural Posterior Estimation [90.21090932619695]
Inferring the parameters of a model based on experimental observations is central to the scientific method. A particularly challenging setting is when the model is strongly indeterminate, i.e., when distinct sets of parameters yield identical observations. We present a method for cracking such indeterminacy by exploiting additional information conveyed by an auxiliary set of observations sharing global parameters.
arXiv Detail & Related papers (2021-02-12T12:23:13Z)
In and out of equilibrium quantum metrology with mean-field quantum criticality [68.8204255655161]
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.
arXiv Detail & Related papers (2020-01-09T19:20:42Z)

This list is automatically generated from the titles and abstracts of the papers in this site.