QUANTUM ENCRYPTION COMMUNICATION METHOD

摘要

A sender (1) adds a decoy photon to a secret photon with secret information, carries out different rotation operations for the photons, and then transmit them to a quantum communication path (3) (S11, S12). A receiver (2) receives the photons, obtains position information of the decoy from the sender (1) through a classical communication path (4); carries out different rotation operations for the decoy and the secret photon using the obtained position information, respectively; change their order; and transmits the same (S13, S14). The sender (1) obtains information of the decoy position and operation amounts from the receiver (2), decodes the decoy; judges no interceptor (5) if a quantum state is consistent with an initial quantum state (S15, S16); and transmits a secret photon in which only encryption coded by itself at the step (S12) is decrypted (S17). The receiver (2) decrypts the encryption made by itself at the step (S13) to obtain the secret information (S18). Thus, not only classical information such as key information but also quantum information can be sent safely. In addition, the detection of an interceptor can be made effectively.