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:2610.11629

Spin-outcome correlations and memory-assisted entropic uncertainty in Bhabha scattering with an entangled spectator

Zan Cao, Meng-Long Song, Xue-Ke Song, Liu Ye, Dong Wang

quant-phhep-thSubmitted Oct 8, 2026• Announced Oct 9, 2026• 0 citations
arXivHTMLPDF

Abstract

We investigate spin-outcome correlations and memory-assisted entropic uncertainty in tree-level Bhabha scattering, where an incident electron $A$ scatters with a positron $B$ initially entangled with a spectator electron $C$. For the fixed-angle post-selected final state, we compare the total memory-assisted uncertainty $U_A$ for three alternative Pauli measurements on $A$ with the entanglement entropy $S(ρ_A)$ across the $A|BC$ partition. We resolve $U_A$ into the separate uncertainties $U_B$ and $U_C$ and evaluate the corresponding outcome-memory mutual-information sums $G_B$ and $G_C$. This separates changes in the randomness of the outcomes on $A$ from changes in their correlations with each memory. In the parameter regions studied, enhanced $A|BC$ entanglement is accompanied by lower $U_A$, most prominently near high-energy backscattering. An analytic treatment of this limit shows that $B$ factorizes from $AC$: $G_B$ vanishes, whereas $G_C$ increases with the initial $B$-$C$ entanglement. An entropic complete complementarity analysis characterizes the accompanying loss of local helicity predictability in $ρ_A$ and changes in the coherence, predictability, and mixedness of the interacting pair $ρ_{AB}$. These results show that initial $B$-$C$ entanglement can lower the total memory-assisted uncertainty in high-energy backscattering by strengthening spin-outcome correlations with the spectator $C$, thereby identifying the distinct roles of the interacting particle and the spectator as quantum memories.

Comments
15 pages,7figures

Related papers

Entanglement distribution in Bhabha scattering with an entangled spectator particle

Massimo Blasone A, Gaetano Lambiase, Bruno Micciola

We analyze how entanglement is generated and distributed in a Bhabha scattering process $({e}^{\ensuremath{-}}{e}^{+}\ensuremath{\rightarrow}{e}^{\ensuremath{-}}{e}^{+})$ at tree level. In our setup an electron $A$ scatters with a positron $B$, which is initially entangled with another electron $C$ (spectator), that does not participate directly to the process. We find that the QED scattering generates and distributes entanglement in a nontrivial way among the three particles; the correlations in the output channels $AB$, $AC$, and $BC$ are studied in detail as functions of the scattering parameters and of the initial entanglement weight. Although derived in a specific case, our results exhibit some general features of other similar QED scattering processes, for which the extension of the present analysis is straightforward.

Physical review. D/Physical review. D.•May 16, 2024•20 citations

Genuine tripartite entanglement in Bhabha scattering with an entangled spectator particle

Zan Cao, Meng-Long Song, Xue-Ke Song +2 more

From the perspective of quantum information science, we investigate tree-level Bhabha scattering between an incident electron $A$ and a positron $B$, where $B$ is initially entangled with a spectator electron $C$, which does not participate in the scattering interaction. We find that the quantum electrodynamics (QED) scattering between $A$ and $B$ can drive the global $ABC$ system into a genuine tripartite entangled (GTE) state. Using four canonical tripartite entanglement metrics, we systematically characterize and quantify the GTE of the composite system, and demonstrate that the scattering momentum of the $A$-$B$ pair and the initial $B$-$C$ entanglement are the key resources governing GTE generation. We further analyze the monogamy of quantum correlations, which imposes fundamental constraints on the shareability of quantum resources in multipartite systems. Specifically, we systematically study the monogamy relations for the squared entanglement of formation and squared quantum discord in our scattering model, and find that monogamy constraints are markedly relaxed in the non-relativistic regime, enabling enhanced shareability of quantum correlations across the three particles. This work uncovers novel quantum correlation properties of fundamental QED scattering processes, and provides direct theoretical guidance for the development of QED-based quantum information processing protocols.

quant-pharXiv:2604.26380•Physical review. D/Physical review. D.•Apr 30, 2026•0 citations

Entanglement distribution in Bhabha scattering with entangled spectator particle

Massimo Blasone A, Gaetano Lambiase, Bruno Micciola

We analyze how entanglement is generated and distributed in a Bhabha scattering process $(e^-e^+\rightarrow e^-e^+)$ at tree level. In our setup an electron $A$ scatters with a positron $B$, which is initially entangled with another electron $C$ (spectator), that does not participate directly to the process. We find that the QED scattering generates and distributes entanglement in a non-trivial way among the three particles: the correlations in the output channels $AB$, $AC$ and $BC$ are studied in detail as functions of the scattering parameters and of the initial entanglement weight. Although derived in a specific case, our results exhibit some general features of other similar QED scattering processes, for which the extension of the present analysis is straightforward.

arXiv:2401.10715•Jan 19, 2024•0 citations

Quantum-memory-assisted entropic uncertainty in spin models with Dzyaloshinskii–Moriya interaction

Zhiming Huang

Abstract In this article, we investigate the dynamics and correlations of quantum-memory-assisted entropic uncertainty, the tightness of the uncertainty, entanglement, quantum correlation and mixedness for various spin chain models with Dzyaloshinskii–Moriya (DM) interaction, including the XXZ model with DM interaction, the XY model with DM interaction and the Ising model with DM interaction. We find that the uncertainty grows to a stable value with growing temperature but reduces as the coupling coefficient, anisotropy parameter and DM values increase. It is found that the entropic uncertainty is closely correlated with the mixedness of the system. The increasing quantum correlation can result in a decrease in the uncertainty, and the robustness of quantum correlation is better than entanglement since entanglement means sudden birth and death. The tightness of the uncertainty drops to zero, apart from slight volatility as various parameters increase. Furthermore, we propose an effective approach to steering the uncertainty by weak measurement reversal.

Laser Physics Letters•Jan 9, 2018•34 citations

Entropic Uncertainty for Two Coupled Dipole Spins Using Quantum Memory under the Dzyaloshinskii–Moriya Interaction

Ahmad N. Khedr, Abdel‐Baset A. Mohamed, Abdel‐Haleem Abdel‐Aty +3 more

-axis, the current study explores the quantum-memory-assisted entropic uncertainty relation (QMA-EUR), entropy mixedness and the concurrence two-spin entanglement. Quantum entanglement is reduced at increased temperature values, but inflation uncertainty and mixedness are enhanced. The considered quantum effects are stabilized to their stationary values at high temperatures. The two-spin entanglement is entirely repressed if the D-M interaction is disregarded, and the entropic uncertainty and entropy mixedness reach their maximum values for equal coupling rates. Rather than the concurrence, the entropy mixedness can be a proper indicator of the nature of the entropic uncertainty. The effect of model parameters (D-M coupling and dipole-dipole spin) on the quantum dynamic effects in thermal environment temperature is explored. The results reveal that the model parameters cause significant variations in the predicted QMA-EUR.

Entropy•Nov 28, 2021•21 citations

Control of quantum memory assisted entropic uncertainty lower bound for topological qubits in open quantum system through environment

Soroush Haseli, Hazhir Dolatkhah, Hossein Rangani Jahromi +2 more

The uncertainty principle is one of the most important issues that clarify the distinction between classical and quantum theory. This principle sets a bound on our ability to predict the measurement outcome of two incompatible observables precisely. Uncertainty principle can be formulated via Shannon entropies of the probability distributions of measurement outcome of the two observables. It has shown that the entopic uncertainty bound can be improved by considering an additional particle as the quantum memory $B$ which has correlation with the measured particle $A$. In this work we consider the memory assisted entropic uncertainty for the case in which the quantum memory and measured particle are topological qubits. In our scenario the topological quantum memory $B$, is considered as an open quantum system which interacts with its surrounding. The motivation for this model is associated with the fact that the basis of the memory-assisted entropic uncertainty relation is constructed on the correlation between quantum memory $B$ and measured particle $A$. In the sense that, Bob who holds the quantum memory $B$ can predict Alice's measurement results on particle $A$ more accurately, when the amount of correlation between $A$ and $B$ is great. Here, we want to find the influence of environmental effects on uncertainty bound while the quantum memory interacts with its surrounding. In this work we will consider Ohmic-like Fermionic and Bosonic environment. We have also investigate the effect of the Fermionic and Bosonic environment on the lower bounds of the amount of the key that can be extracted per state by Alice and Bob for quantum key distribution protocols.

arXiv:1906.05613•Jun 13, 2019•0 citations
We investigate spin-outcome correlations and memory-assisted entropic uncertainty in tree-level Bhabha scattering, where an incident electron AAA scatters with a positron BBB initially entangled with a spectator electron CCC. For the fixed-angle post-selected final state, we compare the total memory-assisted uncertainty UAU_AUA​ for three alternative Pauli measurements on AAA with the entanglement entropy S(ρA)S(ρ_A)S(ρA​) across the A∣BCA|BCA∣BC partition. We resolve UAU_AUA​ into the separate uncertainties UBU_BUB​ and UCU_CUC​ and evaluate the corresponding outcome-memory mutual-information sums GBG_BGB​ and GCG_CGC​. This separates changes in the randomness of the outcomes on AAA from changes in their correlations with each memory. In the parameter regions studied, enhanced A∣BCA|BCA∣BC entanglement is accompanied by lower UAU_AUA​, most prominently near high-energy backscattering. An analytic treatment of this limit shows that BBB factorizes from ACACAC: GBG_BGB​ vanishes, whereas GCG_CGC​ increases with the initial BBB-CCC entanglement. An entropic complete complementarity analysis characterizes the accompanying loss of local helicity predictability in ρAρ_AρA​ and changes in the coherence, predictability, and mixedness of the interacting pair ρABρ_{AB}ρAB​. These results show that initial BBB-CCC entanglement can lower the total memory-assisted uncertainty in high-energy backscattering by strengthening spin-outcome correlations with the spectator CCC, thereby identifying the distinct roles of the interacting particle and the spectator as quantum memories.
We analyze how entanglement is generated and distributed in a Bhabha scattering process $({e}^{\ensuremath{-}}{e}^{+}\ensuremath{\rightarrow}{e}^{\ensuremath{-}}{e}^{+})$ at tree level. In our setup an electron AAA scatters with a positron BBB, which is initially entangled with another electron CCC (spectator), that does not participate directly to the process. We find that the QED scattering generates and distributes entanglement in a nontrivial way among the three particles; the correlations in the output channels ABABAB, ACACAC, and BCBCBC are studied in detail as functions of the scattering parameters and of the initial entanglement weight. Although derived in a specific case, our results exhibit some general features of other similar QED scattering processes, for which the extension of the present analysis is straightforward.
From the perspective of quantum information science, we investigate tree-level Bhabha scattering between an incident electron AAA and a positron BBB, where BBB is initially entangled with a spectator electron CCC, which does not participate in the scattering interaction. We find that the quantum electrodynamics (QED) scattering between AAA and BBB can drive the global ABCABCABC system into a genuine tripartite entangled (GTE) state. Using four canonical tripartite entanglement metrics, we systematically characterize and quantify the GTE of the composite system, and demonstrate that the scattering momentum of the AAA-BBB pair and the initial BBB-CCC entanglement are the key resources governing GTE generation. We further analyze the monogamy of quantum correlations, which imposes fundamental constraints on the shareability of quantum resources in multipartite systems. Specifically, we systematically study the monogamy relations for the squared entanglement of formation and squared quantum discord in our scattering model, and find that monogamy constraints are markedly relaxed in the non-relativistic regime, enabling enhanced shareability of quantum correlations across the three particles. This work uncovers novel quantum correlation properties of fundamental QED scattering processes, and provides direct theoretical guidance for the development of QED-based quantum information processing protocols.
We analyze how entanglement is generated and distributed in a Bhabha scattering process (e−e+→e−e+)(e^-e^+\rightarrow e^-e^+)(e−e+→e−e+) at tree level. In our setup an electron AAA scatters with a positron BBB, which is initially entangled with another electron CCC (spectator), that does not participate directly to the process. We find that the QED scattering generates and distributes entanglement in a non-trivial way among the three particles: the correlations in the output channels ABABAB, ACACAC and BCBCBC are studied in detail as functions of the scattering parameters and of the initial entanglement weight. Although derived in a specific case, our results exhibit some general features of other similar QED scattering processes, for which the extension of the present analysis is straightforward.
Abstract In this article, we investigate the dynamics and correlations of quantum-memory-assisted entropic uncertainty, the tightness of the uncertainty, entanglement, quantum correlation and mixedness for various spin chain models with Dzyaloshinskii–Moriya (DM) interaction, including the XXZ model with DM interaction, the XY model with DM interaction and the Ising model with DM interaction. We find that the uncertainty grows to a stable value with growing temperature but reduces as the coupling coefficient, anisotropy parameter and DM values increase. It is found that the entropic uncertainty is closely correlated with the mixedness of the system. The increasing quantum correlation can result in a decrease in the uncertainty, and the robustness of quantum correlation is better than entanglement since entanglement means sudden birth and death. The tightness of the uncertainty drops to zero, apart from slight volatility as various parameters increase. Furthermore, we propose an effective approach to steering the uncertainty by weak measurement reversal.
-axis, the current study explores the quantum-memory-assisted entropic uncertainty relation (QMA-EUR), entropy mixedness and the concurrence two-spin entanglement. Quantum entanglement is reduced at increased temperature values, but inflation uncertainty and mixedness are enhanced. The considered quantum effects are stabilized to their stationary values at high temperatures. The two-spin entanglement is entirely repressed if the D-M interaction is disregarded, and the entropic uncertainty and entropy mixedness reach their maximum values for equal coupling rates. Rather than the concurrence, the entropy mixedness can be a proper indicator of the nature of the entropic uncertainty. The effect of model parameters (D-M coupling and dipole-dipole spin) on the quantum dynamic effects in thermal environment temperature is explored. The results reveal that the model parameters cause significant variations in the predicted QMA-EUR.
The uncertainty principle is one of the most important issues that clarify the distinction between classical and quantum theory. This principle sets a bound on our ability to predict the measurement outcome of two incompatible observables precisely. Uncertainty principle can be formulated via Shannon entropies of the probability distributions of measurement outcome of the two observables. It has shown that the entopic uncertainty bound can be improved by considering an additional particle as the quantum memory BBB which has correlation with the measured particle AAA. In this work we consider the memory assisted entropic uncertainty for the case in which the quantum memory and measured particle are topological qubits. In our scenario the topological quantum memory BBB, is considered as an open quantum system which interacts with its surrounding. The motivation for this model is associated with the fact that the basis of the memory-assisted entropic uncertainty relation is constructed on the correlation between quantum memory BBB and measured particle AAA. In the sense that, Bob who holds the quantum memory BBB can predict Alice's measurement results on particle AAA more accurately, when the amount of correlation between AAA and BBB is great. Here, we want to find the influence of environmental effects on uncertainty bound while the quantum memory interacts with its surrounding. In this work we will consider Ohmic-like Fermionic and Bosonic environment. We have also investigate the effect of the Fermionic and Bosonic environment on the lower bounds of the amount of the key that can be extracted per state by Alice and Bob for quantum key distribution protocols.