title: Measurement of the entanglement between photonic spatial modes in optical fibers.
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.
authors.affiliation: Korea Research Institute of Standards and Science, Daejeon 305-340, South Korea.
authors.forename: Yoonshik
authors.initials: Y
authors.lastname: Kang
authors.forename: Jaekwon
authors.initials: J
authors.lastname: Ko
authors.forename: Sang Min
authors.initials: SM
authors.lastname: Lee
authors.forename: Sang-Kyung
authors.initials: SK
authors.lastname: Choi
authors.forename: Byoung Yoon
authors.initials: BY
authors.lastname: Kim
authors.forename: Hee Su
authors.initials: HS
authors.lastname: Park