title: Entangled photon generation in two-period quasi-phase-matched parametric down-conversion.
abstract: We proposed and demonstrated a simple but deterministic scheme for generating polarization-entangled photon pairs at telecommunication wavelengths with type-II quasi-phase-matched spontaneous parametric down-conversion (QPM-SPDC) having two poling periods. We fabricated a LiNbO3 crystal having two poling periods so as to generate entangled photons at two wavelengths, i.e., 1506 nm and 1594 nm. We characterized the two-photon polarization state with state tomography and confirmed that the state was highly entangled.
authors.affiliation: Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira,Aoba-ku, Sendai 980-8577, Japan. ueno@quantum.riec.tohoku.ac.jp
authors.forename: Wakana
authors.initials: W
authors.lastname: Ueno
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Kaneda
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Suzuki
authors.forename: Shigehiro
authors.initials: S
authors.lastname: Nagano
authors.forename: Atsushi
authors.initials: A
authors.lastname: Syouji
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Shimizu
authors.forename: Koji
authors.initials: K
authors.lastname: Suizu
authors.forename: Keiichi
authors.initials: K
authors.lastname: Edamatsu
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D007368:Interferometry / Q000295:instrumentation*; D017785:Photons; D013685:Telecommunications / Q000295:instrumentation*