Quantum states characterization for the zero-error capacity
نویسندگان
چکیده
The zero-error capacity of quantum channels was defined as the least upper bound of rates at which classical information is transmitted through a quantum channel with probability of error equal to zero. This paper investigates some properties of input states used to attain the zero-error capacity of quantum channels. Initially, we reformulate the problem of finding the zero-error capacity in the language of graph theory. We use this alternative definition to prove that the zero-error capacity of any quantum channel is reached by using only pure states. PACS numbers: 03.67.-a, 03.67.Hk Submitted to: J. Phys. A: Math. Gen. Quantum states characterization for the zero-error capacity 2
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