The strange correlator has been proposed as way to detect short-range entangled states in one- and two- (and sometimes three-) dimensional systems. It takes the form of a spin-spin correlation function, computed as a mixed overlap between the state of interest and a trivial local product state. An interesting detail is that the strange correlator is computed in the featureless bulk but gives information about the character of the system's edge modes. I'll discuss how one can directly evaluate the strange correlator within the valence bond loop gas framework and give some numerical examples of applications to various Affleck-Kennedy-Lieb-Tasaki (AKTL) states. In particular, I will demonstrate the predicted even-odd effect in the spin value S for the linear-chain and square-lattice AKLT states; and I will present evidence that the diamond-lattice AKLT (unlike the cubic) is a non-trivial symmetry-protected topological state.

Kevin Beach is an MIT-trained physicist and a former Fellow of the Alexander von Humboldt Foundation. Condensed matter physics is his primary area of research, and his work straddles the line between theory and numerics. Kevin Beach joined the Department of Physics and Astronomy at the University of Mississippi in August 2014. He previously held an academic appointment at the University of Alberta.