title: Engineering frequency-time quantum correlation of narrow-band biphotons from cold atoms.
abstract: The nonclassical photon pair, generated via a parametric process, is naturally endowed with a specific form of frequency-time quantum correlations. Here, we report complete control of frequency-time quantum correlations of narrow-band biphotons generated via spontaneous four-wave mixing in a cold atomic ensemble. We have experimentally confirmed the generation of frequency-anticorrelated, frequency-correlated, and frequency-uncorrelated narrow-band biphoton states, as well as verifying the strong nonclassicality of the correlations. Our work opens up new possibilities for engineering narrow-band entangled photons for various quantum optical and quantum information applications.
authors.affiliation: Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea.
authors.forename: Young-Wook
authors.initials: YW
authors.lastname: Cho
authors.affiliation: Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea.
authors.forename: Kwang-Kyoon
authors.initials: KK
authors.lastname: Park
authors.affiliation: Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea.
authors.forename: Jong-Chan
authors.initials: JC
authors.lastname: Lee
authors.affiliation: Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea.
authors.forename: Yoon-Ho
authors.initials: YH
authors.lastname: Kim