Optics and Photonics Society of Iran

In this paper, simulation of the transverse distribution of entangled photon pairs generated by spontaneous parametric down-conversion (SPDC) process is reported. SPDC process is a three-wave mixing that is carried out in a nonlinear crystal and the entangled photon pairs generated by this process to be used in various fields of quantum information such as quantum computing, quantum cryptography and quantum communication. First, we solve the phase matching equations of SPDC process in both of type I and type II phase matching methods inside BBO crystal and then effect of variation of pump angle versus the normal vector to the crystal surface on transverse distribution of the entangled pair photons of signal and idler has been investigated and it has been found that a small change in pump angle leads to a great change in the transverse distribution of signal and idler photons.