Informação Acessível Erro-Zero de Fontes Quânticas

We introduce a new concept called zero-error accessible information of a quantum source which measures the amount of information shared by two parties, one which has a quantum source, and the other which uses a measurement scheme to decode the quantum states received, upon the restriction that no decoding errors must occur. No general method to obtain the accessible information in a general quantum scenario is known and due to that the Holevo upper bound is widely used. However, in the zero-error scenario described, it is possible to determine a closed formula for such measure which coincides with the classical zero-error capacity of an equivalent discrete memoryless channel. The results described increase the understading of Quantum Zero-Error Information Theory and its particularities.