title: Flux enhancement of photons entangled in orbital angular momentum.
abstract: Entangled photons are generally collected by detection systems that select their certain spatial modes, for example using single-mode optical fibers. We derive simple and easy-to-use expressions that allow us to maximize the coupling efficiency of entangled photons with specific orbital angular momentum (OAM) correlations generated by means of spontaneous parametric downconversion. Two different configurations are considered: one in which the beams with OAM are generated by conversion from beams without OAM, and the second when beams with OAM are generated directly from the nonlinear medium. Also, an example of how to generate a maximally entangled qutrit is presented.
authors.affiliation: ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain.
authors.forename: Silvana
authors.initials: S
authors.lastname: Palacios
authors.forename: R de J
authors.initials: Rde J
authors.lastname: León-Montiel
authors.forename: Martin
authors.initials: M
authors.lastname: Hendrych
authors.forename: Alejandra
authors.initials: A
authors.lastname: Valencia
authors.forename: Juan P
authors.initials: JP
authors.lastname: Torres