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arXiv · 1004.4906

Quantum computational renormalization in the Haldane phase

Stephen D. Bartlett·Gavin K. Brennen·Akimasa Miyake·Joseph M. Renes
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Abstract

Single-spin measurements on the ground state of an interacting spin lattice can be used to perform a quantum computation. We show how such measurements can mimic renormalization group transformations and remove the short-ranged variations of the state that can reduce the fidelity of a computation. This suggests that the quantum computational ability of a spin lattice could be a robust property of a quantum phase. We illustrate our idea with the ground state of a spin-1 chain, which can serve as a quantum computational wire not only at the Affleck-Kennedy-Lieb-Tasaki point, but within the rotationally-invariant Haldane phase.

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Stephen D. Bartlett, Gavin K. Brennen, Akimasa Miyake, Joseph M. Renes. 2010-09-10. Quantum computational renormalization in the Haldane phase. https://doi.org/10.1103/physrevlett.105.110502

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