QUANTUM IDENTITY AUTHENTICATION USING GAUSSIAN-MODULATED SQUEEZED STATES

Two continuous-variable quantum identity authentication schemes, which are utilized to prevent active attack, are presented by using Gaussian-modulated squeezed states. The proposed schemes can both verify user's identity as well as distribute an updated new key as the authentication key. A new defined fidelity parameter is proposed to verify the identity of the communicator and detect eavesdropping. The analytical results show the feasibility of these two identity authentication schemes and the security under the attack of general Gaussian-cloner strategy and collective attack.