Interferometer-Free Polarization-Entangled Photon Source Using Single Periodic Domain Structure

Chun-Yao Yang^1,2, Chao-Yuan Wang^1,2*, Kuan-Heng Lin^1,2, Tsung-Ying Tsai^1,2, Chih-Chia Lin^1,2, Li-Bang Wang^1,2, Chih-Sung Chuu^1,2

¹Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
²Center for Quantum Technology, National Tsing Hua University, Hsinchu, Taiwan

* Presenter:Chao-Yuan Wang, email:amamiyayuuko91403@hotmail.com.tw

Polarization-entangled photons are essential to many quantum technologies and fundamental studies. In this paper, we propose and demonstrate a novel method that generates polarization-entangled photons by exploiting single periodic domain structure in a nonlinear crystal to realize two types of phase-matching necessary for the polarization entanglement. The compact source, without the need of interferometers, delicate domain structures, and post-selection, is advantageous for scalable quantum computing and communication, where many replicas or chip-scale devices are needed.

Keywords: Quantum entanglement, Bell inequality, Entangled photons