Rab Adil S, Polino Emanuele, Man Zhong-Xiao, Ba An Nguyen, Xia Yun-Jie, Spagnolo Nicolò, Lo Franco Rosario, Sciarrino Fabio
Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro, 5, Roma, I-00185, Italy.
Shandong Provincial Key Laboratory of Laser Polarization and Information Technology, Department of Physics, Qufu Normal University, Qufu, 273165, China.
Nat Commun. 2017 Oct 13;8(1):915. doi: 10.1038/s41467-017-01058-6.
Wave-particle duality is the most fundamental description of the nature of a quantum object, which behaves like a classical particle or wave depending on the measurement apparatus. On the other hand, entanglement represents nonclassical correlations of composite quantum systems, being also a key resource in quantum information. Despite the very recent observations of wave-particle superposition and entanglement, whether these two fundamental traits of quantum mechanics can emerge simultaneously remains an open issue. Here we introduce and experimentally realize a scheme that deterministically generates entanglement between the wave and particle states of two photons. The elementary tool allowing this achievement is a scalable single-photon setup which can be in principle extended to generate multiphoton wave-particle entanglement. Our study reveals that photons can be entangled in their dual wave-particle behavior and opens the way to potential applications in quantum information protocols exploiting the wave-particle degrees of freedom to encode qubits.Here the authors experimentally realize a scheme that deterministically generates entanglement between the wave and particle states of two photons using a scalable all-optical scheme. They achieve this result by first showing generation of controllable single-photon wave-particle superposition states.
波粒二象性是对量子物体本质的最基本描述，量子物体的行为取决于测量仪器，既可以像经典粒子，也可以像经典波。另一方面，纠缠表示复合量子系统的非经典关联，也是量子信息中的关键资源。尽管最近观察到了波粒叠加和纠缠，但量子力学的这两个基本特性是否能同时出现仍是一个悬而未决的问题。在这里，我们介绍并通过实验实现了一种方案，该方案能确定性地在两个光子的波态和粒子态之间产生纠缠。实现这一成果的基本工具是一种可扩展的单光子装置，原则上它可以扩展以产生多光子波粒纠缠。我们的研究表明，光子可以在其波粒二象性行为中发生纠缠，并为利用波粒自由度来编码量子比特的量子信息协议的潜在应用开辟了道路。在这里，作者通过一种可扩展的全光方案，实验实现了一种能确定性地在两个光子的波态和粒子态之间产生纠缠的方案。他们首先展示了可控单光子波粒叠加态的产生，从而实现了这一结果。
