English
Related papers

Related papers: Assessing the quantumness of a damped two-level sy…

200 papers

We highlight the existence of a joint probability distribution as the common underpinning assumption behind Bell-type, contextuality, and Leggett-Garg-type tests. We then present a procedure to translate contextual scenarios into temporal…

Quantum Physics · Physics 2016-10-13 M. Markiewicz , P. Kurzynski , J. Thompson , S. -Y. Lee , A. Soeda , T. Paterek , D. Kaszlikowski

We show that in some cases the coherent state can have a larger violation of the Leggett-Garg inequality (LGI) than the cat state by numerical calculations. To achieve this result, we consider the LGI of the cavity mode weakly coupled to a…

Quantum Physics · Physics 2021-07-13 Hiroo Azuma , Masashi Ban

The evolution of a two-level system subjected to stimulated transitions which is undergoing a sequence of measurements of the level occupation probability is evaluated. Its time correlation function is compared to the one obtained through…

Quantum Physics · Physics 2009-10-30 Tommaso Calarco , Roberto Onofrio

The connection between the Leggett-Garg inequality and optimal scenarios from the point of view of quantum metrology is investigated for perfect and noisy general dichotomic measurements. In this context, we show that the Fisher information…

In 1985, Leggett and Garg put forward the concept of macroscopic realism (macrorealism) and, in analogy to Bell's theorem, derived a necessary condition in terms of inequalities, which are now known as the Leggett-Garg inequalities. In this…

Quantum Physics · Physics 2013-05-15 Johannes Kofler , Caslav Brukner

We discuss quantum evolution of a decaying state in relation to a recent experiment of Katz et al. Based on exact analytical and numerical solutions of a simple model, we identify a regime where qubit retains coherence over a finite time…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Leonid P. Pryadko , Alexander N. Korotkov

Self-testing of quantum devices based on observed measurement statistics is a method to certify quantum systems using minimal resources. In Ref. [Phys. Rev. \textbf{A} 101, 032106 (2020)], a scheme based on observing measurement statistics…

Quantum Physics · Physics 2024-12-03 Chellasamy Jebarathinam , Gautam Sharma , Sk Sazim , Remigiusz Augusiak

We study Leggett-Garg inequalities (LGIs) for a two level system (TLS) undergoing Markovian dynamics described by unital maps. We find analytic expression of LG parameter $K_{3}$ (simplest variant of LGIs) in terms of the parameters of two…

Quantum Physics · Physics 2023-04-25 Sayan Ghosh , Anant V. Varma , Sourin Das

We present a detailed report on the decoherence of quantum states of continuous variable systems under the action of a quantum optical master equation resulting from the interaction with general Gaussian uncorrelated environments. The rate…

Quantum Physics · Physics 2007-05-23 A. Serafini , M. G. A. Paris , F. Illuminati , S. De Siena

We prove a no-go theorem for a class of hidden variables theories that satisfy parameter independence. Specifically, we show that, assuming two conditions, there are no non-trivial hidden variables models of the quantum predictions for…

Quantum Physics · Physics 2014-04-29 Guido Bacciagaluppi

The Leggett-Garg (LG) inequalities were introduced, as a temporal parallel of the Bell inequalities, to test macroscopic realism -- the view that a macroscopic system evolving in time possesses definite properties which can be determined…

Quantum Physics · Physics 2020-01-08 J. J. Halliwell

Various measures have been suggested recently for quantifying the coherence of a quantum state with respect to a given basis. We first use two of these, the l_1-norm and relative entropy measures, to investigate tradeoffs between the…

Quantum Physics · Physics 2015-10-08 Shuming Cheng , Michael J. W. Hall

The Leggett-Garg inequality is a widely used test of the "quantumness" of a system, and involves correlations between measurements realized at different times. According to its widespread interpretation, a violation of the Legget-Garg…

Quantum Physics · Physics 2016-01-07 Saulo V. Moreira , Arne Keller , Thomas Coudreau , Perola Milman

By using geometric measure of discord (\texttt{GMOD})[Phys. Rev. Lett, 105, 109502 (2010)] and measurement-induced nonlocality (\texttt{MIN})[Phys. Rev. Lett, 106, 120401 (2011)], we investigate quantum correlation of a pair of two-level…

Quantum Physics · Physics 2015-06-03 Guo-Feng Zhang , Heng Fan , Ai-Ling Ji , Wu-Ming Liu

We investigate Leggett-Garg temporal inequalities in flavor-mixing processes. We derive an exact flavor-mass uncertainty product and we establish that it is an upper bound to the violation of the inequalities. This finding relates temporal…

Quantum Physics · Physics 2021-12-10 Massimo Blasone , Fabrizio Illuminati , Luciano Petruzziello , Luca Smaldone

Irreversible behaviour is traditionally associated with open stochastic dynamical systems, but an asymmetry in the probabilistic specification of a closed deterministic system can similarly lead to a disparity between the likelihoods of a…

Quantum Physics · Physics 2018-09-03 Claudia L. Clarke , Ian J. Ford

We investigate the violation of the Leggett-Garg inequalities for a harmonic oscillator in various quantum states. We focus on the two-time quasi-probability distribution function with a dichotomic variable constructed with the position…

In the cryptographic context, an earlier unexplored application of the temporal version of the Bell-type inequality is shown here in the device-independent (DI) scenario. This is done by using the Leggett-Garg inequality (LGI) to…

Quantum Physics · Physics 2016-02-25 Akshata Shenoy H. , S. Aravinda , R. Srikanth , D. Home

Using detailed balance and scaling properties of integrals that appear in the Coulomb gas reformulation of quantum impurity problems, we establish exact relations between the nonequilibrium quantum decay rates of the boundary sine-Gordon…

Statistical Mechanics · Physics 2016-08-31 Holger Baur , Andrea Fubini , Ulrich Weiss

The present work is devoted to the characterization of the Leggett-Garg inequality for three-flavoured neutrino oscillations in presence of both matter and Charge-Conjugation and Parity violating (CP) effects. This study complements and…

High Energy Physics - Phenomenology · Physics 2019-05-08 Javid Naikoo , Ashutosh Kumar Alok , Subhashish Banerjee , S. Uma Sankar