The Effect of the Number of Entangled Photons on the Number of Coincidences Rate, Bell’s Inequality and the Error Rate by the Delphi Program

Quantum cryptography is a science that relies on the use of a protocol designed to exploit quantum mechanical phenomena to achieve the secrecy of cryptographic keys. This work aimed to generate a quantum key based on polarization-entangled photon pairs; to eliminate the error by implementing the BB89 protocol using the Delphi language program in order to obtain a high degree of security. The results explain the effect of the number of EPR photons pair running from (500-10000) photons on the number of coincidences, expected error and Bell's parameter discussed as; Total coincidences of the Bell – CHSH increases with increasing of EPR pairs, and values were stable when EPR pairs were increased, there was a small random change in the expected error rate (in case of no eavesdropping).This study concludes thatTotal coincidences of the Bell and expected error are affected by the number of entangled photons.The increasing of the length of key must increase the number of EPR and decrease the Error and Bell's value must be stable.