821 research outputs found
Enhancement of quantum correlations for the system of cavity QED by applying bang-bang pulses
We propose a scheme of increasing quantum correlations for the cavity quantum
electrodynamics system consisting of two noninteracting two-level atoms each
locally interacting with its own quantized field mode by bang-bang pulses. We
investigate the influence of the bang-bang pulses on the dynamics of quantum
discord, entanglement, quantum mutual information and classical correlation
between the two atoms. It is shown that the amount of quantum discord and
entanglement of the two atoms can be improved by applying the bang-bang pulses.Comment: 6 pages, 5 figure
A 4 Gb/s 2-level to 2 Gsymbol/s 4-level converter GaAs IC for semiconductor optical amplifier QPSK modulators
Maximally entangled mixed states of two atoms trapped inside an optical cavity
In some off-resonant cases, the reduced density matrix of two atoms
symmetrically coupled with an optical cavity can very approximately approach to
maximally entangled mixed states or maximal Bell violation mixed states in
their evolution. The influence of phase decoherence on the generation of
maximally entangled mixed state is also discussed.
PACS numbers: 03.67.-a, 03.65.UdComment: 7 pages, 4 figures, Latex, have a major revision of content
4 Gb/s two-level to 2 symbol/s four-level converter GaAs IC for semiconductor optical amplifier modulators
Non-Markovian effect on the quantum discord
We study the non-Markovian effect on the dynamics of the quantum discord by
exactly solving a model consisting of two independent qubits subject to two
zero-temperature non-Markovian reservoirs, respectively. Considering the two
qubits initially prepared in Bell-like or extended Werner-like states, we show
that there is no occurrence of the sudden death, but only instantaneous
disappearance of the quantum discord at some time points, in comparison to the
entanglement sudden death in the same range of the parameters of interest. It
implies that the quantum discord is more useful than the entanglement to
describe quantum correlation involved in quantum systems.Comment: 5 pages, 5 figure
Quantum discord dynamical behaviors due to initial system-cavity correlations
We analyze the roles of initial correlations between the two-qubit system and
a dissipative cavity on quantum discord dynamics of two qubits. Considering two
initial system-cavity states, we show that the initial system-cavity
correlations not only can initially increase the two-qubit quantum discord but
also would lead to a larger long-time quantum discord asymptotic value.
Moreover, quantum discord due to initial correlations is more robust than the
case of the initial factorized state. Finally, we show the initial
correlations' importance for dynamics behaviors of mutual information and
classical correlation
Describing distribution and density patterns of metamorphosed 0- and 1-group cod related to hydrographical conditions, physical frontal zones, and bottom topography using hydroacoustic and trawl sampling methods in the Central Baltic Sea
Control the entanglement of two atoms in an optical cavity via white noise
Two two-level atoms within a leaky optical cavity is driven by two
independent external optical white noise fields. We investigate how
entanglement between two atoms arises in such a situation. The steady state
entanglement of two atoms is also investigated. A stochastic-resonance-like
behavior of entanglement is revealed. Finally, the Bell violation between atoms
is discussed.Comment: 10 pages, 9 figure
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