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Quantum Information Processing with Low-Dimensional Systems

Alexander Yu. Vlasov
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Abstract

A `register' in quantum information processing -- is composition of k quantum systems, `qudits'. The dimensions of Hilbert spaces for one qudit and whole quantum register are d and d^k respectively, but we should have possibility to prepare arbitrary entangled state of these k systems. Preparation and arbitrary transformations of states are possible with universal set of quantum gates and for any d may be suggested such gates acting only on single systems and neighbouring pairs. Here are revisited methods of construction of Hamiltonians for such universal set of gates and as a concrete new example is considered case with qutrits. Quantum tomography is also revisited briefly.

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Alexander Yu. Vlasov. 2005-12-05. Quantum Information Processing with Low-Dimensional Systems. https://arxiv.org/abs/quant-ph/0512034

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