We propose a spin-independent scheme to generate and detect two-particle entanglement in a mesoscopic normal-superconductor system. A superconductor, weakly coupled to the normal conductor, generates an orbitally entangled state by injecting pairs of electrons into different leads of the normal conductor. The entanglement is detected via violation of a Bell inequality, formulated in terms of zero-frequency current cross correlators. It is shown that the Bell inequality can be violated for arbitrary strong dephasing in the normal conductor.We propose a spin-independent scheme to generate and detect two-particle entanglement in a mesoscopic normal-superconductor system. A superconductor, weakly coupled to the normal conductor, generates an orbitally entangled state by injecting pairs of electrons into different leads of the normal conductor. The entanglement is detected via violation of a Bell inequality, formulated in terms of zero-frequency current cross correlators. It is shown that the Bell inequality can be violated for arbitrary strong dephasing in the normal conductor.

arXiv:cond-mat/0303531Physical Review LettersOct 9, 2003239 citations

Range of violations of Bell's inequality by entangled photon pairs

Frederick M. Kronz

Physics Letters AFeb 1, 20011 citation

Maximally entangled states and the Bell inequality

Jose Luis Cereceda

arXiv:quant-ph/9812012Physics Letters AMar 1, 19968 citations

Bell nonlocality and entanglement in $χ_{cJ}$ decays into baryon pairBell nonlocality and entanglement in $χ_{cJ}$ decays into baryon pair

PengCheng Hong, RongGang Ping, WeiMin Song

We present a systematic analysis of Bell nonlocality and entanglement in $χ_{cJ}$ ( $J=0,1,2$ ) decays into baryon pair( $B\bar{B}$ ), with particular emphasis on their production via the process $e^+e^- \to ψ(2S) \to γχ_{cJ}$ at BESIII. From the baryon-antibaryon spin density matrix, we construct measurable Bell observables and concurrence, revealing a striking hierarchy of quantum correlations: $χ_{c0}$ decays exhibit maximal violation and entanglement; $χ_{c1}$ decays violate Bell inequalities for $θ_1 \in (0, π)$ with angle-modulated strength; we find that the $B\bar{B}$ pair in $χ_{c2}$ decays is in a separable state, and no indication of Bell inequality violation is observed. We provide complete analytical results for $J=0,1$ and quantitative, uncertainty-aware estimations for $J=2$ based on experimental inputs from BESIII. These results establish the $χ_{cJ}$ system produced via this radiative transition as a novel and promising platform for testing quantum entanglement and Bell nonlocality in high-energy collisions.We present a systematic analysis of Bell nonlocality and entanglement in $χ_{cJ}$($J=0,1,2$) decays into baryon pair($B\bar{B}$), with particular emphasis on their production via the process $e^+e^- \to ψ(2S) \to γχ_{cJ}$ at BESIII. From the baryon-antibaryon spin density matrix, we construct measurable Bell observables and concurrence, revealing a striking hierarchy of quantum correlations: $χ_{c0}$ decays exhibit maximal violation and entanglement; $χ_{c1}$ decays violate Bell inequalities for $θ_1 \in (0, π)$ with angle-modulated strength; we find that the $B\bar{B}$ pair in $χ_{c2}$ decays is in a separable state, and no indication of Bell inequality violation is observed. We provide complete analytical results for $J=0,1$ and quantitative, uncertainty-aware estimations for $J=2$ based on experimental inputs from BESIII. These results establish the $χ_{cJ}$ system produced via this radiative transition as a novel and promising platform for testing quantum entanglement and Bell nonlocality in high-energy collisions.

hep-phCross-listedarXiv:2512.22837Physical review. D/Physical review. D.Dec 30, 20251 citation

Particle Physics—Bell Inequalities

Reinhold A. Bertlmann, Nicolai Friis

Abstract In this chapter we review the phenomenology of K mesons, or kaons, and the possibility of Bell-inequality violation in systems of K-meson pairs. To this end we first study their properties and features: strangeness represented by the strange quark, the violation of the charge-conjugation parity (CP) symmetry, strangeness oscillation, and regeneration. These interesting phenomena emerge from the fact that the strangeness eigenstates, CP eigenstates, and mass eigenstates are not the same, as well as from the interplay of the strangeness-conserving and CP-conserving strong interaction and the weak interaction which violates these conservation rules. We then examine the quasi-spin analogy of K mesons and the correlation functions for entangled K-meson pairs. After concluding that the physical measurements possible for K-mesons do not allow a direct violation of Bell inequalities such as the Uchiyama-Bell inequality we identify the CP violation as an indirect violation of Bell inequalities.Abstract In this chapter we review the phenomenology of K mesons, or kaons, and the possibility of Bell-inequality violation in systems of K-meson pairs. To this end we first study their properties and features: strangeness represented by the strange quark, the violation of the charge-conjugation parity (CP) symmetry, strangeness oscillation, and regeneration. These interesting phenomena emerge from the fact that the strangeness eigenstates, CP eigenstates, and mass eigenstates are not the same, as well as from the interplay of the strangeness-conserving and CP-conserving strong interaction and the weak interaction which violates these conservation rules. We then examine the quasi-spin analogy of K mesons and the correlation functions for entangled K-meson pairs. After concluding that the physical measurements possible for K-mesons do not allow a direct violation of Bell inequalities such as the Uchiyama-Bell inequality we identify the CP violation as an indirect violation of Bell inequalities.

Sep 7, 20230 citations

Bell nonlocality and entanglement in

χ_{cJ}

decays into baryon pair

We present a systematic analysis of Bell nonlocality and entanglement in

χ_{cJ}

(

J=0,1,2

) decays into baryon pair(

B\bar{B}

), with particular emphasis on their production via the process

e^+e^- \to ψ(2S) \to γχ_{cJ}

at BESIII. From the baryon-antibaryon spin density matrix, we construct measurable Bell observables and concurrence, revealing a striking hierarchy of quantum correlations:

χ_{c0}

decays exhibit maximal violation and entanglement;

χ_{c1}

decays violate Bell inequalities for

θ_1 \in (0, π)

with angle-modulated strength; we find that the

B\bar{B}

pair in

χ_{c2}

decays is in a separable state, and no indication of Bell inequality violation is observed. We provide complete analytical results for

J=0,1

and quantitative, uncertainty-aware estimations for

J=2

based on experimental inputs from BESIII. These results establish the

χ_{cJ}

system produced via this radiative transition as a novel and promising platform for testing quantum entanglement and Bell nonlocality in high-energy collisions.