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:2406.09542

Correlating two qubits via common cavity environment

Amit Dey

Published Jun 13, 2024• 0 citations
arXivHTMLPDF

Abstract

Generation of quantum entanglement between a pair of qubits is studied in a cavity-QED platform. The qubit pair is placed inside a common cavity environment. We show that the relative strength of qubit-photon couplings is crucial for establishing inter-qubit entanglement. Resonance as well as off-resonance between the qubits and photon are considered . For off-resonant case we detect a threshold value of coupling ratio, beyond which maximally entangled state is always available. The resonant case displays interesting non-monotonic behavior, where the maximum entanglement peaks at an intermediate coupling ratio. The driven-dissipative dynamics of our model exhibits non-trivial dependence of steady-state entanglement on the drive strength.

DOI
10.48550/arxiv.2406.09542

Related papers

Correlating two qubits via a common cavity

Amit Dey

Generation of quantum entanglement between a pair of qubits is studied in a cavity-QED platform. The qubit pair is placed inside a common cavity environment. We show that the relative strength of qubit-photon couplings is crucial for establishing interqubit entanglement. Resonance as well as off resonance between the qubits and photon are considered. For the off-resonant case we detect a threshold value of the coupling ratio, beyond which the maximally entangled state is always available. The resonant case displays interesting nonmonotonic behavior, where the maximum entanglement peaks at an intermediate coupling ratio. The driven-dissipative dynamics of our model exhibits nontrivial dependence of steady-state entanglement on the drive strength.

Physical Review A•Apr 3, 2025•4 citations

Entanglement in a driven two-qubit system coupled to common cavity

Amit Dey

A system, comprised of a qubit pair coupled to a common cavity, is studied with the aim of establishing qubit entanglement. This study is the sequel of the paper Phys. Rev. A 111, 043705 (2025), where similar model was investigated for an initially vacuum cavity. In the present manuscript the cavity with finite initial occupancy is considered and the effect of asymmetric qubit cavity couplings is investigated. For a closed system scenario, the ratio of the qubit-cavity couplings shows a threshold beyond which no maximally-entangled qubit state is available. The threshold value is shown to depend on the excitation level of the cavity. For a driven-dissipative case steady state entanglement is shown to depend non-monotonically on the qubit drive. Intricate interplay of drive, dissipation, and coupling asymmetry is shown to be pivotal for steady-state entanglement generation.

quant-pharXiv:2603.20866•Mar 24, 2026•0 citations

Off-resonant entanglement generation in a lossy cavity

Francesco Francica, Sabrina Maniscalco, PIILO J +2 more

We provide an analytical description of the entanglement dynamics of two qubits coupled to a common structured reservoir at zero temperature. We derive the conditions to maximize reservoir-induced entanglement for an initially factorized state of the two-qubit system. In particular, when the two qubits are placed inside a lossy cavity, we show that high values of entanglement can be obtained, even in the bad-cavity limit, in the dispersive regime. Finally we show that, under certain conditions, the entanglement dynamics exhibits quantum beats and we explain their physical origin in terms of the interference between two different transitions coupling the dressed states of the system.

•Jan 1, 2009•0 citations

Off-resonant entanglement generation in a lossy cavity

Francesco Francica, Sabrina Maniscalco, Jyrki Piilo +2 more

We provide an analytical description of the entanglement dynamics of two qubits coupled to a common structured reservoir at zero temperature. We derive the conditions to maximize reservoir-induced entanglement for an initially factorized state of the two-qubit system. In particular, when the two qubits are placed inside a lossy cavity, we show that high values of entanglement can be obtained, even in the bad-cavity limit, in the dispersive regime. Finally we show that, under certain conditions, the entanglement dynamics exhibits quantum beats and we explain their physical origin in terms of the interference between two different transitions coupling the dressed states of the system.

arXiv:0812.1886•Physical Review A•Mar 11, 2009•56 citations

Entanglement and bistability in coupled quantum dots inside a driven cavity

Arnab Mitra, Reeta Vyas

Generation and dissipation of entanglement between two coupled quantum dots (QDs) in a cavity driven by a coherent field is studied. We find that it is possible to generate and sustain a large amount of entanglement between the quantum dots in the steady state, even in the presence of strong decay in both the cavity and the dots. We investigate the effect of different parameters (decay rates, coupling strengths, and detunings) on entanglement. We find that the cavity field shows bistability and study the effect of relevant parameters on the existence of this bistable behavior. We also study the correlation between the cavity field and the entanglement between the dots. The experimental viability of the proposed scheme is discussed.

Physical Review A•Jan 28, 2010•15 citations

Atom-field entanglement in cavity QED: Nonlinearity and saturation

Robert Rogers, Nick Cummings, Leno M. Pedrotti +1 more

We investigate the degree of entanglement between an atom and a driven cavity mode in the presence of dissipation. Previous work has shown that in the limit of weak driving fields, the steady-state entanglement is proportional to the square of the driving intensity. This quadratic dependence is due to the generation of entanglement by the creation of pairs of photons or excitations. In this work we investigate the entanglement between an atom and a cavity in the presence of multiple photons. Nonlinearity of the atomic response is needed to generate entanglement, but as that nonlinearity saturates the entanglement vanishes. We posit that this is due to spontaneous emission, which puts the atom in the ground state and the atom-field state into a direct product state. An intermediate value of the driving field, near the field that saturates the atomic response, optimizes the atom-field entanglement. In a parameter regime for which multiphoton resonances occur, we find that entanglement recurs at those resonances. In this regime, we find that the entanglement decreases with increasing photon number. We also investigate, in the bimodal regime, the entanglement as a function of atom and/or cavity detuning. Here we find that there is evidence of a phase transition in the entanglement, which occurs at $2\ensuremath{\epsilon}/g\ensuremath{\ge}1$.

arXiv:1512.00936•Physical Review A•Nov 8, 2017•17 citations
Generation of quantum entanglement between a pair of qubits is studied in a cavity-QED platform. The qubit pair is placed inside a common cavity environment. We show that the relative strength of qubit-photon couplings is crucial for establishing inter-qubit entanglement. Resonance as well as off-resonance between the qubits and photon are considered . For off-resonant case we detect a threshold value of coupling ratio, beyond which maximally entangled state is always available. The resonant case displays interesting non-monotonic behavior, where the maximum entanglement peaks at an intermediate coupling ratio. The driven-dissipative dynamics of our model exhibits non-trivial dependence of steady-state entanglement on the drive strength.
Generation of quantum entanglement between a pair of qubits is studied in a cavity-QED platform. The qubit pair is placed inside a common cavity environment. We show that the relative strength of qubit-photon couplings is crucial for establishing interqubit entanglement. Resonance as well as off resonance between the qubits and photon are considered. For the off-resonant case we detect a threshold value of the coupling ratio, beyond which the maximally entangled state is always available. The resonant case displays interesting nonmonotonic behavior, where the maximum entanglement peaks at an intermediate coupling ratio. The driven-dissipative dynamics of our model exhibits nontrivial dependence of steady-state entanglement on the drive strength.
A system, comprised of a qubit pair coupled to a common cavity, is studied with the aim of establishing qubit entanglement. This study is the sequel of the paper Phys. Rev. A 111, 043705 (2025), where similar model was investigated for an initially vacuum cavity. In the present manuscript the cavity with finite initial occupancy is considered and the effect of asymmetric qubit cavity couplings is investigated. For a closed system scenario, the ratio of the qubit-cavity couplings shows a threshold beyond which no maximally-entangled qubit state is available. The threshold value is shown to depend on the excitation level of the cavity. For a driven-dissipative case steady state entanglement is shown to depend non-monotonically on the qubit drive. Intricate interplay of drive, dissipation, and coupling asymmetry is shown to be pivotal for steady-state entanglement generation.
We provide an analytical description of the entanglement dynamics of two qubits coupled to a common structured reservoir at zero temperature. We derive the conditions to maximize reservoir-induced entanglement for an initially factorized state of the two-qubit system. In particular, when the two qubits are placed inside a lossy cavity, we show that high values of entanglement can be obtained, even in the bad-cavity limit, in the dispersive regime. Finally we show that, under certain conditions, the entanglement dynamics exhibits quantum beats and we explain their physical origin in terms of the interference between two different transitions coupling the dressed states of the system.
We provide an analytical description of the entanglement dynamics of two qubits coupled to a common structured reservoir at zero temperature. We derive the conditions to maximize reservoir-induced entanglement for an initially factorized state of the two-qubit system. In particular, when the two qubits are placed inside a lossy cavity, we show that high values of entanglement can be obtained, even in the bad-cavity limit, in the dispersive regime. Finally we show that, under certain conditions, the entanglement dynamics exhibits quantum beats and we explain their physical origin in terms of the interference between two different transitions coupling the dressed states of the system.
Generation and dissipation of entanglement between two coupled quantum dots (QDs) in a cavity driven by a coherent field is studied. We find that it is possible to generate and sustain a large amount of entanglement between the quantum dots in the steady state, even in the presence of strong decay in both the cavity and the dots. We investigate the effect of different parameters (decay rates, coupling strengths, and detunings) on entanglement. We find that the cavity field shows bistability and study the effect of relevant parameters on the existence of this bistable behavior. We also study the correlation between the cavity field and the entanglement between the dots. The experimental viability of the proposed scheme is discussed.
We investigate the degree of entanglement between an atom and a driven cavity mode in the presence of dissipation. Previous work has shown that in the limit of weak driving fields, the steady-state entanglement is proportional to the square of the driving intensity. This quadratic dependence is due to the generation of entanglement by the creation of pairs of photons or excitations. In this work we investigate the entanglement between an atom and a cavity in the presence of multiple photons. Nonlinearity of the atomic response is needed to generate entanglement, but as that nonlinearity saturates the entanglement vanishes. We posit that this is due to spontaneous emission, which puts the atom in the ground state and the atom-field state into a direct product state. An intermediate value of the driving field, near the field that saturates the atomic response, optimizes the atom-field entanglement. In a parameter regime for which multiphoton resonances occur, we find that entanglement recurs at those resonances. In this regime, we find that the entanglement decreases with increasing photon number. We also investigate, in the bimodal regime, the entanglement as a function of atom and/or cavity detuning. Here we find that there is evidence of a phase transition in the entanglement, which occurs at $2\ensuremath{\epsilon}/g\ensuremath{\ge}1$.