0000000000614952

AUTHOR

Erika Andersson

showing 3 related works from this author

Revival of quantum correlations without system-environment back-action

2010

Revivals of quantum correlations have often been explained in terms of back-action on quantum systems by their quantum environment(s). Here we consider a system of two independently evolving qubits, each locally interacting with a classical random external field. The environments of the qubits are also independent, and there is no back-action on the qubits. Nevertheless, entanglement, quantum discord and classical correlations between the two qubits may revive in this model. We explain the revivals in terms of correlations in a classical-quantum state of the environments and the qubits. Although classical states cannot store entanglement on their own, they can play a role in storing and rev…

PhysicsQuantum PhysicsQuantum discordBell stateCluster stateFOS: Physical sciencesQuantum entanglementQuantum PhysicsAtomic and Molecular Physics and OpticsSettore FIS/03 - Fisica Della MateriaEntanglementOpen quantum systemQuantum mechanicsOpen quantum systemStatistical physicsW stateAmplitude damping channelQuantum Physics (quant-ph)Quantum teleportationquantum correlation
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Dynamics of correlations due to a phase noisy laser

2012

We analyze the dynamics of various kinds of correlations present between two initially entangled independent qubits, each one subject to a local phase noisy laser. We give explicit expressions of the relevant quantifiers of correlations for the general case of single-qubit unital evolution, which includes the case of a phase noisy laser. Although the light field is treated as classical, we find that this model can describe revivals of quantum correlations. Two different dynamical regimes of decay of correlations occur, a Markovian one (exponential decay) and a non-Markovian one (oscillatory decay with revivals) depending on the values of system parameters. In particular, in the non-Markovia…

Physics03.67.Mn Entanglement measures witnesses and other characterizationQuantum discordQuantum PhysicsPhase (waves)Markov processFOS: Physical sciencesQuantum entanglement03.65.Ud Entanglement and quantum nonlocality (e.g. EPR paradox Bell's inequalities GHZ states etc.)Condensed Matter PhysicsAtomic and Molecular Physics and OpticsSettore FIS/03 - Fisica Della Materiasymbols.namesake02.50.Ga Markov processeQubit42.50.Dv Quantum state engineering and measurementsymbolsStatistical physicsExponential decayQuantum Physics (quant-ph)QuantumMathematical PhysicsLight field03.67.Lx Quantum computation architectures and implementations03.65.Ud Entanglement and quantum nonlocality (e.g. EPR paradox Bell's inequalities GHZ states etc.); 42.50.Dv Quantum state engineering and measurements; 03.67.Mn Entanglement measures witnesses and other characterizations; 02.50.Ga Markov processes; 03.67.Lx Quantum computation architectures and implementations
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Experimental recovery of quantum correlations in absence of system-environment back-action

2013

Revivals of quantum correlations in composite open quantum systems are a useful dynamical feature against detrimental effects of the environment. Their occurrence is attributed to flows of quantum information back and forth from systems to quantum environments. However, revivals also show up in models where the environment is classical, thus unable to store quantum correlations, and forbids system-environment back-action. This phenomenon opens basic issues about its interpretation involving the role of classical environments, memory effects, collective effects and system-environment correlations. Moreover, an experimental realization of back-action-free quantum revivals has applicative rele…

PhysicsMultidisciplinaryQuantum decoherenceSettore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciGeneral Physics and AstronomyNanotechnologyGeneral ChemistryQuantum entanglementclassical environments no back-actionSudden deathArticleGeneral Biochemistry Genetics and Molecular BiologyAction (physics)Flow (mathematics)quantum informationOpen quantum systemStatistical physicsQuantumquantum correlation
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