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arXiv · 0802.4314

Identifying phases of quantum many-body systems that are universal for quantum computation

Andrew C. Doherty·Stephen D. Bartlett
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Abstract

Quantum computation can proceed solely through single-qubit measurements on an appropriate quantum state, such as the ground state of an interacting many-body system. We investigate a simple spin-lattice system based on the cluster-state model, and by using nonlocal correlation functions that quantify the fidelity of quantum gates performed between distant qubits, we demonstrate that it possesses a quantum (zero-temperature) phase transition between a disordered phase and an ordered "cluster phase" in which it is possible to perform a universal set of quantum gates.

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Andrew C. Doherty, Stephen D. Bartlett. 2009-07-16. Identifying phases of quantum many-body systems that are universal for quantum computation. https://doi.org/10.1103/physrevlett.103.020506

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