Optimal coupling of entangled photons into single-mode optical fibers

ICL, Londinium, England, United Kingdom
Optics Express (Impact Factor: 3.53). 08/2004; 12(14):3264-9. DOI: 10.1364/OPEX.12.003264
Source: arXiv

ABSTRACT We present a consistent multimode theory that describes the coupling of single photons generated by collinear Type-I parametric downconversion into single-mode optical fibers. We have calculated an analytic expression for the fiber diameter which maximizes the pair photon count rate. For a given focal length and wavelength, a lower limit of the fiber diameter for satisfactory coupling is obtained.

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