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We show that a suitably engineered external non-Gaussian noise can entangle a class of initially separable, polarized two-photon coherent states.

A new technique of an entangled photon pair generation and regeneration characterization using an all fiber optic scheme is investigated. The proposed system is consisted of a fiber optic ring resonator. The Kerr nonlinearity effect in the fiber ring resonator is exploited for the generation of two independent beams. The advantage of such a system is that it requires a simple arrangement without any optical pumping part and bulky optical components. Polarized light pulse trains are launched randomly into a nonlinear fiber optic ring resonator. Where the superpositions of light pulses in a nonlinear fiber optics ring resonator are randomly occurred which is formed the entangled photon pairs. A polarization controller controls polarization states of light pulses while circulating in the ring resonator. The entangled photons are seen on the avalanche photo-detector. Then the output of the entangled photon states recovery by using a fiber ring resonator incorporating an erbium-doped fiber (EDF) has been investigated. We have shown that the weak entangled photon states can be recovered after circulating in the amplified fiber optic medium. The results obtained have shown that this system can be used to achieve the recovered polarization entangled states with the obtained high gain. The amplifying noise has also been detected and seen on the spectrum output. This is affected to the entangled photon visibility, which is discussed.

We propose an experiment based on statistical analysis to test the currently accepted statement, that “a photon cannot be split.” The essential statistical phenomenon pertains not only to beam splitters, but also to the generation of correlated photon pairs used extensively in quantum optics experiments. A consequence of this analysis is that, arguably the tactic of reducing the window defining a coincidence has the unexpected effect of preferentially selecting uncorrelated photon pairs, thereby undermining an essential prerequisite for the conclusions drawn from such experiments.