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On the Measurement of Two-Photon Single-Mode Coupling Efficiency in Parametric Down-Conversion Photon Sources
Published
Author(s)
Stefania Castelletto, Ivo P. Degiovanni, Alan L. Migdall, M J. Ware
Abstract
Photon-based quantum information schemes have increased the need for light sources that produce individual photons, with many such schemes relying on optical parametric downconversion (PDC). Practical realizations of this technology require that the PDC light be collected into a single spatial mode defined by an optical fiber. We present two possible models describing single mode fibers coupling to PDC light fields in a non-collinear configuration, that lead to two different results. This is a general approach, including factors like crystal length, and walk-off, non collinear phase-matching, and transverse pump field distribution. We propose an experimental test to distinguish between the two. The goal is to help clarify open issues, such as how to extend the theory beyond the simplest experimental arrangements, and more importantly, to improve the collection efficiency.
Castelletto, S.
, Degiovanni, I.
, Migdall, A.
and Ware, M.
(2004),
On the Measurement of Two-Photon Single-Mode Coupling Efficiency in Parametric Down-Conversion Photon Sources, New Journal of Physics, [online], https://doi.org/10.1088/1367-2630/6/1/087, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=841786
(Accessed October 14, 2025)