Measurement-based quantum computation in a 2D phase of matter
  Recently it has been shown that the non-local correlations needed for measurement based quantum computation (MBQC) can be revealed in the ground state of the Affleck-Kennedy-Lieb-Tasaki (AKLT) model involving nearest neighbor spin-3/2 interactions on a honeycomb lattice. This state is not singular but resides in the disordered phase of ground states of a large family of Hamiltonians characterized by short-range-correlated valence bond solid states. By applying local filtering and adaptive single particle measurements we show that most states in the disordered phase can be reduced to a graph of correlated qubits that is a scalable resource for MBQC. At the transition between the disordered and Neel ordered phases we find a transition from universal to non-universal states as witnessed by the scaling of percolation in the reduced graph state. 
Andrew S. Darmawan, Gavin K. Brennen, and Stephen D. Bartlett
quant-ph cond-mat.str-el