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arXiv · 1401.3504

Corner contribution to the entanglement entropy of an O(3) quantum critical point in 2+1 dimensions

Ann B. Kallin·E. M. Stoudenmire·Paul Fendley·Rajiv R. P. Singh·Roger G. Melko
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Abstract

The entanglement entropy for a quantum critical system across a boundary with a corner exhibits a sub-leading logarithmic scaling term with a scale-invariant coefficient. Using a Numerical Linked Cluster Expansion, we calculate this universal quantity for a square-lattice bilayer Heisenberg model at its quantum critical point. We find, for this 2+1 dimensional O(3) universality class, that it is thrice the value calculated previously for the Ising universality class. This relation gives substantial evidence that this coefficient provides a measure of the number of degrees of freedom of the theory, analogous to the central charge in a 1+1 dimensional conformal field theory.

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Ann B. Kallin, E. M. Stoudenmire, Paul Fendley, Rajiv R. P. Singh, Roger G. Melko. 2014-02-19. Corner contribution to the entanglement entropy of an O(3) quantum critical point in 2+1 dimensions. https://doi.org/10.1088/1742-5468%2F2014%2F06%2Fp06009

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