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arXiv · 0807.4797

Transitions in the computational power of thermal states for measurement-based quantum computation

Sean D. Barrett·Stephen D. Bartlett·Andrew C. Doherty·David Jennings·Terry Rudolph
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Abstract

We show that the usefulness of the thermal state of a specific spin-lattice model for measurement-based quantum computing exhibits a transition between two distinct "phases" - one in which every state is a universal resource for quantum computation, and another in which any local measurement sequence can be simulated efficiently on a classical computer. Remarkably, this transition in computational power does not coincide with any phase transition, classical or quantum, in the underlying spin-lattice model.

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Sean D. Barrett, Stephen D. Bartlett, Andrew C. Doherty, David Jennings, Terry Rudolph. 2008-07-30. Transitions in the computational power of thermal states for measurement-based quantum computation. https://doi.org/10.1103/physreva.80.062328

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