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Related papers: Quantum Zeno effect in parameter estimation

200 papers

We summarise important recent advances in quantum metrology, in connection to experiments in cold gases, trapped cold atoms and photons. First we review simple metrological setups, such as quantum metrology with spin squeezed states, with…

Quantum Physics · Physics 2015-01-27 Geza Toth , Iagoba Apellaniz

Quantum Zeno and anti-Zeno effects on pure dephasing are studied using exactly solvable microscopic models. The crossover between these two opposite effects is investigated. The case of a single two-level system undergoing dephasing is…

Quantum Physics · Physics 2014-02-24 Adam Zaman Chaudhry , Jiangbin Gong

Various schemes have been proposed to overcome the drawback of the decoherence on quantum-enhanced parameter estimation. Here we suggest an alternative method, quantum feedback, to enhance the parameter precision of optimal quantum…

Quantum Physics · Physics 2015-06-24 Qiang Zheng , Li Ge , Yao Yao , Qi-jun Zhi

The quantum Zeno evolution of a quantum system takes place in a proper subspace of the total Hilbert space. The physical and mathematical features of the "Zeno subspaces" depend on the measuring apparatus: when this is included in the…

Quantum Physics · Physics 2017-08-23 P. Facchi , S. Pascazio

The quantum-Zeno and anti-Zeno effects (QZE/AZE) are known for a long time, in a quantum system with coupled levels, the measurement of a particular level population can lead to either acceleration (i.e. AZE) or retardation (i.e. QZE) of…

Quantum Physics · Physics 2023-08-22 Jacob Levitt , Artur F. Izmaylov

In few-qubit systems, the quantum Zeno effect arises when measurement occurs sufficiently frequently that the spins are unable to relax between measurements. This can compete with Hamiltonian terms, resulting in interesting relaxation…

Strongly Correlated Electrons · Physics 2025-02-05 Umar Javed , Riccardo J. Valencia-Tortora , Jamir Marino , Vadim Oganesyan , Michael Kolodrubetz

A continuous measurement of energy which is sharp (perfect) leads to the quantum Zeno effect (freezing of the state). Only if the quantum measurement is fuzzy, continuous monitoring gives a readout E(t) from which information about the…

Quantum Physics · Physics 2009-10-30 Jürgen Audretsch , Michael Mensky

We study the quantum Zeno effect in the case of indirect measurement, where the detector does not interact directly with the unstable system. Expanding on the model of Koshino and Shimizu [Phys. Rev. Lett., 92, 030401, (2004)] we consider a…

Quantum Physics · Physics 2009-11-10 M. G. Makris , P. Lambropoulos

We perform stochastic simulations of the quantum Zeno and anti-Zeno effects for two level system and for the decaying one. Instead of simple projection postulate approach, a more realistic model of a detector interacting with the…

Quantum Physics · Physics 2007-05-23 J. Ruseckas , B. Kaulakys

We experimentally demonstrate the freezing of evolution of quantum states in one- and two-dimensional subspaces of two qubits, on an NMR quantum information processor. State evolution was frozen and leakage of the state from its subspace to…

Quantum Physics · Physics 2014-12-03 Harpreet Singh , Arvind , Kavita Dorai

The measurements in the optical test of quantum Zeno effect [Itano et al. Phys. Rev. A\underbar{41} (1990) 2295) are analyzed using the environment-induced decoherence theory, where the spontaneous emission lifetime of the relevant level…

Quantum Physics · Physics 2009-09-25 Anu Venugopalan , R. Ghosh

We study the estimation of a single parameter characterizing families of unitary transformations acting on two systems. We consider the situation with the presence of bottleneck, i.e. only one of the systems can be measured to gather…

Quantum Physics · Physics 2020-10-06 Milajiguli Rexiti , Stefano Mancini

The quantum Zeno and anti-Zeno paradigms have thus far addressed the evolution control of a quantum system coupled to an immutable bath via non-selective measurements performed at appropriate intervals. We fundamentally modify these…

In this paper it is proposed the dynamical quantum Zeno Effect in quantum decision theory. The measurement postulate is not an essential ingredient for the explanation of the quantum Zeno effect, a dynamical account is given in quantum…

Quantum Physics · Physics 2021-03-09 R. Rossi

We calculate the quantum Fisher information for a generic many-body fermionic system in a pure state depending on a parameter. We discuss the situations where the parameter is imprinted in the basis states, in the state coefficients, or…

Quantum Physics · Physics 2023-03-21 Olivier Giraud , Mark-Oliver Goerbig , Daniel Braun

We study the measurement process by treating classical detectors entirely quantum mechanically. As a generic model we use a point-contact detector coupled to an electron in a quantum dot and tunneling into the continuum. Transition to the…

Quantum Physics · Physics 2007-05-23 S. A. Gurvitz

A scheme is proposed to estimate the system and environmental parameter, the detuning, temperature and the squeezing strength with a high precision by the two-level atom system. It hasn't been reported that the squeezing strength estimation…

Quantum Physics · Physics 2021-05-07 Mengmeng Luo , Wenxiao Liu , Yuetao Chen , Shaoyan Gao

We study the coexistence of the quantum Zeno effect and non-Markovianity for a system decaying in a structured bosonic environment and subject to a control field. The interaction with the environment induces decay from the excited to the…

Quantum Physics · Physics 2016-02-04 Antti Karlsson , Francesco Francica , Jyrki Piilo , Francesco Plastina

Efficient quantum sensing technologies rely on precise control of quantum sensors, particularly two-level systems or qubits, to optimize estimation processes. We here exploit the Quantum Zeno Effect (QZE) as a tool for maximizing…

Quantum Physics · Physics 2024-10-08 Bruno Ronchi , Analia Zwick , Gonzalo A. Alvarez

We study the quantum Zeno effect (QZE) in two many-body systems, namely the one-dimensional transverse-field Ising model and the Lipkin-Meshkov-Glick (LMG) model, coupled to a central qubit. Our result shows that in order to observe QZE in…

Strongly Correlated Electrons · Physics 2015-05-28 Wing Chi Yu , Li-Gang Wang , Shi-Jian Gu , Hai-Qing Lin