Referent: Fernando de Melo (Leuven)

Tytuł referatu: Noisy One-Way Quantum Computations: The Role of Correlations

Streszczenie: Since the advent of quantum computation, entanglement, a clear-cut quantum mechanical feature, is commonly believed the key resource behind it. Not surprisingly, the importance of correlations for quantum computations has been a much debated subject. For pure state quantum computations certainly some entanglement is necessary if the quantum protocol is not to be efficiently simulated by classical means. The realistic scenario for mixed state quantum computations is, however, far more subtle. In this talk I'll present a general scheme to access the quality of noisy quantum computations within the one-way model. In this model the creation of entanglement and its use as a resource are clearly separated, which then allow us to address the following questions: “Does higher entanglement always empower better computations?”; “Should one always try to minimize the influence of the environment over the entanglement such as to maximize the quality of a computation?”