Southwest Quantum Information and Technology

Uncloneable encryption

Presenting Author: Anne Broadbent, University of Ottawa
Contributing Author(s): Sebastien Lord, University of Ottawa

In 2002, Gottesman answered this question in the positive, proposing a quantum encryption scheme for classical messages, with a decryption process that detects any attempt to copy the ciphertext. Clearly, classical information alone does not allow such a functionality, since it is always possible to perfectly copy a classical ciphertext while avoiding detection. However, Gottesman left open the question of restricting the knowledge that two recipients could simultaneously have on a plaintext, after an attack on a single ciphertext. Here, we address this open question by showing that Wiesner's conjugate coding can be used to achieve this type of uncloneable encryption for classical messages. Our approach is a prepare-and-measure scheme and the analysis is done in the quantum random oracle model, using techniques from the analysis of monogamy-of-entanglement games.

(Session 2 : Sunday from 10:45am - 11:30am)