Physical limitations on quantum nonlocality in the detection of gamma photons emitted from positron/electron annihilation

(n,m,p)型量子网络配置及其非局域性

$(n,m,p)$-type quantum network configuration and its nonlocality

本文提出一种通用的(n,m,p)型无环量子网络配置，推导其n局域关联不等式，并通过纠缠源和泡利测量验证其非n局域性。

Picosecond Timing Resolution Detection of Gamma Photons Utilizing Microchannel-plate Detectors: Experimental Tests of Quantum Nonlocality and Photon Localization

The concept and subsequent experimental verification of the proportionality between pulse amplitude and detector transit time for microchannel plate detectors is presented. This discovery has led to considerable improvement in the overall timing resolution for detection of high energy gamma photons. Utilizing a 22Na positron source, a full width half maximum (FWHM) timing resolution of 138 ps has been achieved. This FWHM includes detector transit-time spread for both chevron-stack type detectors, timing spread due to uncertainties in annihilation location, all electronic uncertainty, and any r…

BESIII中$e^{+}e^{-} \ ightarrow Y\ar{Y}$的贝尔非定域性与纠缠

Bell nonlocality and entanglement in $e^{+}e^{-} \rightarrow Y\bar{Y}$ at BESIII

本文提出一种系统方法研究BESIII中正负电子湮灭产生的自旋1/2超子-反超子系统的量子关联，发现其非定域性运动学区域比$τ^{+}τ^{-}$系统更受限，并给出了探测实验方案。

关于量子纠缠与非局域性

On Quantum Entanglement and Nonlocality

本文通过贝尔不等式探讨量子纠缠与非局域性，指出光子偏振的本地因果性可解释贝尔测试结果，且光子滤波器相互作用不违反相对论。

电子-正电子湮灭中超子-反超子系统的量子导引与量子失协

Quantum steering and discord in hyperon-antihyperon system in electron-positron annihilation

本文基于X形自旋密度矩阵研究电子-正电子湮灭产生的超子-反超子对中的量子导引与失协，揭示极化效应导致的关联行为差异，并部分验证量子关联层级关系。

Nonlocal field correlations and dynamical Casimir-Polder forces between one excited- and two ground-state atoms

The problem of nonlocality in the dynamical three-body Casimir-Polder interaction between an initially excited and two ground-state atoms is considered. It is shown that the nonlocal spatial correlations of the field emitted by the excited atom during the initial part of its spontaneous decay may become manifest in the three-body interaction. The observability of this new phenomenon is discussed.

History and Physics of the Klein Paradox

The early papers by Klein, Sauter and Hund which investigate scattering off a high step potential in the context of the Dirac equation are discussed to derive the 'paradox' first obtained by Klein. The explanation of this effect in terms of electron-positron production is reassessed. It is shown that a potential well or barrier in the Dirac equation can become supercritical and emit positrons or electrons spontaneously if the potential is strong enough. If the well or barrier is wide enough, a seemingly constant current is emitted. This phenomenon is transient whereas the tunnelling first calc…

Two-photon Annihilation of Positrons with K-shell Electrons of H-like ions

The two-photon annihilation of a positron with an electron bound in the 1s state of a H-like ion is calculated within the fully relativistic QED framework. The interaction with the nucleus is treated nonperturbatively, thus allowing the calculations to be carried out for the annihilation with strongly-bound inner shells of heavy ions. Infrared divergences, appearing when one of the emitted photons approaches the low-frequency limit, are accurately eliminated from final expressions. The total cross section of the two-photon and one-photon annihilation processes are compared for a wide range of …

On the Question of Interference in Radiation Produced by Relativistic Channeled Particles

Two approaches used in the description of the channeling radiation emitted from relativistic positrons are compared with each other. In the first (traditional) case, the probability of the process is proportional to a sum of absolute squares of the amplitudes of the transition between two states with definite transverse energy levels of the positrons traversing single crystals. In the second case, we begin with calculation of the sum of amplitudes for transition between states with different transverse energy levels for corresponding radiation frequency, and then the sum is squared. One must k…

通过基于POVM的康普顿偏振度量检验电子-正电子湮灭产生的光子的贝尔测试

Bell Test of Photons from Electron-Positron Annihilation via POVM-based Compton Polarimetry

本文提出利用康普顿偏振度量和POVM框架研究高能光子偏振纠缠，通过多次交互逐步逼近理想投影测量，实现对CHSH不等式的实验违反。

正负电子湮灭中的超子-反超子系统作为含局域与全局退相的温度估计量子探针

Hyperon-antihyperon system in electron-positron annihilation as quantum probes for temperature estimation with local and global dephasing

本研究利用双量子比特探针在欧姆型储库中开展量子测温，分析了最优估计条件、不同储库环境下QFI与QSNR的特性，对比了估计策略优劣，并探究了超子-反超子系统的量子关联特性，为量子测温提供了参考。

Real-time ghost imaging of Bell-nonlocal entanglement between a photon and a quantum memory

Certification of nonlocality of quantum mechanics is an important fundamental test that typically requires prolonged data collection and is only revealed in an in-depth analysis. These features are often particularly exposed in hybrid systems, such as interfaces between light and atomic ensembles. Certification of entanglement from images acquired with single-photon camera can mitigate this issue by exploiting multiplexed photon generation. Here we demonstrate this feature in a quantum memory (QM) operating in a real-time feedback mode. Through spatially-multimode spin-wave storage the QM enab…

湮灭光子的纠缠

Entanglement of annihilation photons

本研究通过康普顿偏振计实验直接比较了正负电子湮灭光子对在纠缠态与可分离态下的偏振关联，发现两者角分布和贝尔关联函数相同，质疑了贝尔定理的普适性。

电子-正电子碰撞中tau轻子对的量子相干非局域优势

Nonlocal advantage of quantum coherence in tau-lepton pairs from electron--positron collisions

本文研究电子-正电子碰撞中tau轻子对的量子相干非局域优势，提出专用见证者，估算Belle II和FCC-ee实验灵敏度，并首次设计高能碰撞器中的引导博弈实现方案。