2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/91001A new quantum cryptography protocol, based on all unselected states of a qubit as a sort of alphabet with continuous set of letters, is proposed. Its effectiveness is calculated and shown to be essentially higher than those of the other known protocols.14 pages, 3 figures, RevTeX, submitted to J. Optics B: Quantum and Semiclassical Optics (special issue to follow the IQEC-2002)Quantum Physicstext