Resource quality of a symmetry-protected topologically ordered phase for quantum computation

Phys Rev Lett. 2015 Mar 27;114(12):120506. doi: 10.1103/PhysRevLett.114.120506. Epub 2015 Mar 26.

Abstract

We investigate entanglement naturally present in the 1D topologically ordered phase protected with the on-site symmetry group of an octahedron as a potential resource for teleportation-based quantum computation. We show that, as long as certain characteristic lengths are finite, all its ground states have the capability to implement any unit-fidelity one-qubit gate operation asymptotically as a key computational building block. This feature is intrinsic to the entire phase, in that perfect gate fidelity coincides with perfect string order parameters under a state-insensitive renormalization procedure. Our approach may pave the way toward a novel program to classify quantum many-body systems based on their operational use for quantum information processing.