Physical Review Letters
Measurement of the Entanglement between Photonic Spatial Modes in Optical Fibers
Yoonshik Kang, Jaekwon Ko, Sang Min Lee, Sang-Kyung Choi, Byoung Yoon Kim, Hee Su Park
Abstract
We experimentally demonstrate the entanglement of spatial modes between two photons propagating through separate few-mode optical fibers. Quantum states over the two lowest-order spatial modes are measured with highly efficient spatial-mode analyzers based on acousto-optics. Quantum state tomography verifies the entanglement of the spatial-domain Bell state.