PROCEDIMIENTO Y EQUIPO DE AUTENTICACION DE CONTRASENAS CUANTICAS

摘要

The invention relates to a method and user device that can be used to verify that two users share a password c of p bits without revealing any information about the password. For this purpose, the method comprises encoding the XOR function of password c with a random sequence a in the quantum state of a single photon. The Hong-Ou-Mandel effect is used in each user device to compare a locally generated quantum state with a state provided by the other user. After n verification phases, the users can determine if the other user knows the password. The method and the user device include techniques for detecting dishonest participants. The invention also relates to the device which performs the method and includes two coding techniques in quantum systems, namely: one based on temporal coding, and another based on coding in the angular orbital momentum of a photon.