Generation of pure single-photon states via spontaneous four-wave mixing in nanofibers with a variable cross section

Abstract

A theory of single-photon sources of light is developed on the basis of spontaneous four-wave mixing in optical nanofibers. The spectral amplitude of the biphoton field is calculated with allowance for the real geometry of a nanofiber manufactured from standard optical fiber by heating and stretching. It is shown that by selecting pump parameters, we can simultaneously obtain the high spectral brightness and low frequency correlation of generated biphoton states in a nondegenerate mode of four-wave mixing that corresponds to single-photon states with the high purity.