Entangled photon generation using a fiber optic Mach-Zehnder interferometer incorporating the nonlinear effect in a fiber ring resonator

A new system for entangled photon-pair generation using an all-fiber optic scheme consists of a fiber optic Mach-Zehnder interferometer (MZI) incorporating a fiber optic ring resonator. The Kerr nonlinearity effect in the fiber ring resonator is exploited for the generation of two independent squeezed beams. The advantage of such a system is that it requires a simple arrangement without any optical pumping parts or bulky optical components. Polarized light pulse trains are launched randomly into a MZI, and one part of the light is delayed in the longer path. The output pulses from both arms of the MZI enter a fiber optic ring resonator. A polarization controller controls the polarization states of the light pulses while they circulate in the ring resonator. The superposition of the nonlinear light pulses in a fiber optic ring resonator randomly occur. These forms are seen on an avalanche photodetector. The results are in good agreement with previous work.