Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1409.1475 · Physical Review A

Quantum correlation and entanglement between an ionizing system and a neighboring atom interacting directly and via a quantized field

Vlasta Peřinová, A. Lukš, J. Křepelka, Jan Peřina

Published Sep 30, 2014• 12 citations
arXivHTMLPDF

Abstract

Quantum correlations between two neighboring atoms are studied. It is assumed that one atomic system comprises a single auto-ionizing level and the other atom does not contain any auto-ionizing level. The excitation of both atoms is achieved by the interaction with the same mode of the quantized field. It is shown that the long-time behavior of two atoms exhibits quantum correlations even when the atoms do not interact directly. This can be shown using the optical excitation of the neighboring atom. Also a measure of entanglement of two atoms can be applied after reduction of the continuum to two levels.

DOI
10.1103/physreva.90.033428

Related papers

Quantum Theory of Atom Field Interaction

Pradip Narayan Ghosh

The coupling of two or more quantum mechanical states representing two different quantum mechanical systems leads to a new class of quantum mechanical states called entangled states. In this case, a two level atom, coupled to a single mode quantized electromagnetic field, results in the dressed state. The Dressed State is an example of Entangled States. This state exhibits a quantum correlation between the two entities, atom and field. The interaction energy of the atom and the quantized field can be written, in the dipolar interaction case, in the same way as in the semi classical theory. The emission of a photon by an atom creates an electromagnetic field that can act with the atom itself. An atom in the excited state, in the absence of a field, decays exponentially with time. This is Wigner Weisskopf model for spontaneous emission.

CRC Press eBooks•Feb 19, 2018•0 citations

Dynamics of quantum correlations for two mode entangled coherent fields

Tesfay Gebremariam Tesfahannes, Ye‐Xiong Zeng, Chong Li

We investigate the quantum correlation dynamics of two separated continuous variable systems for which, the system comprises a pair of two-level atoms coupled to two cavities. Particularly, we consider two initially separable (non-entangled) states and Werner states which locally interact with two mode entangled coherent fields. We found that the atoms with different quantum correlation significantly affects the dynamics of quantum correlation of the fields, and the entanglement of the atoms can enhance the correlations between the field modes. Finally, we show the effect of the purity of initial states on the correlations between the field modes.

Results in Physics•Jan 1, 2017•5 citations

Entanglement dynamics of second quantized quantum fields

Mikhail Erementchouk, Michael Niklaus Leuenberger

We study the entanglement dynamics in the system of coupled quantum fields. We prove that if the coupling is linear, that is if the total Hamiltonian is a quadratic form of field operators, entanglement can only be transferred between the fields. We show that entanglement is produced in the model of the two-mode self-interacting boson field with the characteristic Gaussian decay of coherence in the limit of high number of particles. The interesting feature of this system is that the particles in different modes become entangled even if there is no direct interaction between the modes. We apply these results for analysis of the entanglement dynamics in the two-mode Jaynes-Cummings model in the limit of large number of photons. While the photon-atom interaction is assumed to conserve helicity the photons with different polarizations still get entangled due to an effective interaction mediated by the atom with the characteristic entanglement time linearly increasing with the number of photons.

arXiv:1001.4354•Jan 25, 2010•0 citations

Entanglement Dynamics of a Moving Two-level Atom in a Quantized Field

Jun Zhang

The entanglement dynamics of a two-level atom with center-of-mass motion in a single-mode quantized field is investigated.The behavior of the entropy changes of the subsystems,as well as the concurrence of the coupled atom-field system is explored.These results show that when the atom is initially prepared in ground state anti-correlation behavior occurs,but a positively correlated behavior appears gradually as the increasing of the probability of the atom initially in excited state.Also,the amplitude of the concurrence increases with the increasing of the probability of the atom initially in excited state.In addition,with increasing of the atomic center-of-mass motion,both the amplitudes of the partial entropy changes and the concurrence are reduced.

Shinjang dashösi ilmiy jurnili•Jan 1, 2010•0 citations

Cross-correlations and Entanglement in Cavity QED

Matthew L. Terraciano

Every quantum system subjected to measurements is an open quantum system. The cavity QED system is elegant in that it probes the interaction between two quantum systems, the atom and the field, while its loss mechanisms are well understood and can be externally monitored. The study of cross-correlations in cavity QED is important for understanding how entanglement evolves in open quantum systems. As quantum information science grows we need to learn more about entanglement and how it can be quantified and measured. Correlation functions have been used to compare an electromagnetic field (intensity) of one mode with the electromagnetic field (intensity) of the same mode at a later time or different spatial location. In quantum optics, correlation functions have been calculated and measured to probe the nonclassical field that results from the interaction of a single mode of the electromagnetic field and an ensemble of two-level atoms (the canonical cavity QED system). This field can exhibit antibunching, squeezing, and can violate inequalities required for a classical field. Entanglement in the steady state of a cavity QED system cannot be measured directly with traditional correlation functions (Hanbury-Brown and Twiss type experiments). Cross-correlations, however, interrogate directly both modes of the entangled pair, the transmitted (cavity) and the fluorescent (atom) intensities, and can act as an entanglement witness. This thesis presents the implementation of a cross-correlation measurement in a cavity QED system. The work has required the construction of an apparatus that incorporates laser cooling and trapping with quantum optics to carefully control both the external (center of mass motion) and internal (atomic state) degrees of freedom of a collection of atoms that interact with a single mode of a high finesse Fabry-Perot cavity. We examine theoretically and experimentally a new intensity cross-correlation function which probes the evolution of the cavity field conditioned on the detection of a fluorescent photon from an atom in the cavity. The results open the possibility to generalize the dynamics of entanglement as a physical resource necessary for the nascent quantum information science.

•Jun 30, 2006•0 citations

Entanglement dynamics between a pair of two-level atoms and cavity fields connected by an optical fiber

Sayed Ali Sina Musavi

In this study, we theoretically investigate a system composed of two isolated two-level atoms, each confined within an independent single-mode optical cavity. The cavities are coherently coupled via an optical fiber, enabling photon-mediated interaction between the two subsystems. Each cavity sustains a single-mode quantized electromagnetic field, and each atom couples exclusively to the field within its respective cavity. We analyze the time dependent entanglement dynamics, exploring both atom-atom and cavity-field bipartite entanglement under this hybrid interaction framework. To quantify entanglement, we employ concurrence as the measurement metric. The effects of the atoms' initial states and the optical fiber’s coupling strength on both atom-atom and field-field entanglement are analyzed. Numerical results reveal that when the coupling strength of the optical fiber is close to zero, no entanglement is observed between either the atoms or the fields. However, as the fiber coupling strength increases, entanglement emerges and exhibits collapse and revival behavior over time.

International Journal of Natural Sciences and Mathematics•Aug 24, 2026•0 citations
Quantum correlations between two neighboring atoms are studied. It is assumed that one atomic system comprises a single auto-ionizing level and the other atom does not contain any auto-ionizing level. The excitation of both atoms is achieved by the interaction with the same mode of the quantized field. It is shown that the long-time behavior of two atoms exhibits quantum correlations even when the atoms do not interact directly. This can be shown using the optical excitation of the neighboring atom. Also a measure of entanglement of two atoms can be applied after reduction of the continuum to two levels.
The coupling of two or more quantum mechanical states representing two different quantum mechanical systems leads to a new class of quantum mechanical states called entangled states. In this case, a two level atom, coupled to a single mode quantized electromagnetic field, results in the dressed state. The Dressed State is an example of Entangled States. This state exhibits a quantum correlation between the two entities, atom and field. The interaction energy of the atom and the quantized field can be written, in the dipolar interaction case, in the same way as in the semi classical theory. The emission of a photon by an atom creates an electromagnetic field that can act with the atom itself. An atom in the excited state, in the absence of a field, decays exponentially with time. This is Wigner Weisskopf model for spontaneous emission.
We investigate the quantum correlation dynamics of two separated continuous variable systems for which, the system comprises a pair of two-level atoms coupled to two cavities. Particularly, we consider two initially separable (non-entangled) states and Werner states which locally interact with two mode entangled coherent fields. We found that the atoms with different quantum correlation significantly affects the dynamics of quantum correlation of the fields, and the entanglement of the atoms can enhance the correlations between the field modes. Finally, we show the effect of the purity of initial states on the correlations between the field modes.
We study the entanglement dynamics in the system of coupled quantum fields. We prove that if the coupling is linear, that is if the total Hamiltonian is a quadratic form of field operators, entanglement can only be transferred between the fields. We show that entanglement is produced in the model of the two-mode self-interacting boson field with the characteristic Gaussian decay of coherence in the limit of high number of particles. The interesting feature of this system is that the particles in different modes become entangled even if there is no direct interaction between the modes. We apply these results for analysis of the entanglement dynamics in the two-mode Jaynes-Cummings model in the limit of large number of photons. While the photon-atom interaction is assumed to conserve helicity the photons with different polarizations still get entangled due to an effective interaction mediated by the atom with the characteristic entanglement time linearly increasing with the number of photons.
The entanglement dynamics of a two-level atom with center-of-mass motion in a single-mode quantized field is investigated.The behavior of the entropy changes of the subsystems,as well as the concurrence of the coupled atom-field system is explored.These results show that when the atom is initially prepared in ground state anti-correlation behavior occurs,but a positively correlated behavior appears gradually as the increasing of the probability of the atom initially in excited state.Also,the amplitude of the concurrence increases with the increasing of the probability of the atom initially in excited state.In addition,with increasing of the atomic center-of-mass motion,both the amplitudes of the partial entropy changes and the concurrence are reduced.
Every quantum system subjected to measurements is an open quantum system. The cavity QED system is elegant in that it probes the interaction between two quantum systems, the atom and the field, while its loss mechanisms are well understood and can be externally monitored. The study of cross-correlations in cavity QED is important for understanding how entanglement evolves in open quantum systems. As quantum information science grows we need to learn more about entanglement and how it can be quantified and measured. Correlation functions have been used to compare an electromagnetic field (intensity) of one mode with the electromagnetic field (intensity) of the same mode at a later time or different spatial location. In quantum optics, correlation functions have been calculated and measured to probe the nonclassical field that results from the interaction of a single mode of the electromagnetic field and an ensemble of two-level atoms (the canonical cavity QED system). This field can exhibit antibunching, squeezing, and can violate inequalities required for a classical field. Entanglement in the steady state of a cavity QED system cannot be measured directly with traditional correlation functions (Hanbury-Brown and Twiss type experiments). Cross-correlations, however, interrogate directly both modes of the entangled pair, the transmitted (cavity) and the fluorescent (atom) intensities, and can act as an entanglement witness. This thesis presents the implementation of a cross-correlation measurement in a cavity QED system. The work has required the construction of an apparatus that incorporates laser cooling and trapping with quantum optics to carefully control both the external (center of mass motion) and internal (atomic state) degrees of freedom of a collection of atoms that interact with a single mode of a high finesse Fabry-Perot cavity. We examine theoretically and experimentally a new intensity cross-correlation function which probes the evolution of the cavity field conditioned on the detection of a fluorescent photon from an atom in the cavity. The results open the possibility to generalize the dynamics of entanglement as a physical resource necessary for the nascent quantum information science.
In this study, we theoretically investigate a system composed of two isolated two-level atoms, each confined within an independent single-mode optical cavity. The cavities are coherently coupled via an optical fiber, enabling photon-mediated interaction between the two subsystems. Each cavity sustains a single-mode quantized electromagnetic field, and each atom couples exclusively to the field within its respective cavity. We analyze the time dependent entanglement dynamics, exploring both atom-atom and cavity-field bipartite entanglement under this hybrid interaction framework. To quantify entanglement, we employ concurrence as the measurement metric. The effects of the atoms' initial states and the optical fiber’s coupling strength on both atom-atom and field-field entanglement are analyzed. Numerical results reveal that when the coupling strength of the optical fiber is close to zero, no entanglement is observed between either the atoms or the fields. However, as the fiber coupling strength increases, entanglement emerges and exhibits collapse and revival behavior over time.