Estado binomial no interferômetro de Mach-Zehnder.

Abstract

The quantum cryptography is the future of secure communication, the _rst protocol using the quantum theory is the BB84 which can be applied using polarization or phase. In the case of phase this communication can be made using the Mach-Zehnder quantum interferometer to make superposition of photons and provide security in communication due to the uncertainty in the phase of the detected photons. The number state, that is the state of single photons, is the ideal case for commu- nication, where the phase is unde_ned and with maximum uncertainty. On the other hand, the coherent state is the most usual and can have a satisfactory uncertainty in phase, however is not a state to secure communication, because it is a state regarded classic light. The binomial state is a state interpolator between the coherent state and number state, this interpolation is achieved through the appropriate limits on parameters that de_nes them. With this is possible to have a non-classical state that allows having greater uncertainty in phase and with more satisfactory results than found for the coherent.