Ham Byoung S
Department of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, Gwangju, 61005, South Korea.
Sci Rep. 2025 Mar 31;15(1):10950. doi: 10.1038/s41598-025-95739-8.
Polarization-entangled photon pairs generated from second-order nonlinear optical media have been extensively studied for both fundamental research and potential applications of quantum information. In a spontaneous parametric down-conversion process, quantum entanglement between paired photons, often regarded as 'mysterious,' has been demonstrated for local randomness and nonlocal correlation through polarization-basis projections using linear optics (Phys. Rev. A 60, R773 (1999)). Unlike the conventional particle nature-based perspective, this paper presents a coherence analysis rooted in the wave nature of quantum mechanics to examine these well-established quantum phenomena, incorporating polarization control of the paired photons and their projection measurements. First, we analyze the quantum superposition of photon pairs generated randomly from cross-sandwiched nonlinear media, focusing on local randomness, which depends on the incoherence among measured events. Second, we investigate coincidence detection between paired photons to understand the nonlocal correlation arising from independently controlled remote parameters, resulting in an inseparable product-basis relationship. This coherence-based approach sheds light on a deterministic perspective on quantum features, emphasizing the significance of phase information intrinsic to the wave nature of photons, which is incompatible with the particle nature.
由二阶非线性光学介质产生的偏振纠缠光子对，已被广泛研究用于量子信息的基础研究和潜在应用。在自发参量下转换过程中，通过使用线性光学的偏振基投影，已证明配对光子之间的量子纠缠（通常被视为“神秘的”）具有局部随机性和非局部相关性（《物理评论A》60，R773 (1999)）。与基于传统粒子性质的观点不同，本文提出了一种基于量子力学波动性质的相干分析，以研究这些已确立的量子现象，其中纳入了配对光子的偏振控制及其投影测量。首先，我们分析从交叉夹层非线性介质中随机产生的光子对的量子叠加，重点关注局部随机性，它取决于测量事件之间的不相干性。其次，我们研究配对光子之间的符合检测，以理解由独立控制的远程参数产生的非局部相关性，从而产生一种不可分割的乘积基关系。这种基于相干的方法揭示了对量子特征的确定性观点，强调了光子波动性质所固有的相位信息的重要性，这与粒子性质不相容。
