Emergence of robust gaps in two-dimensional antiferromagnets via additional spin-1/2 probes

  title={Emergence of robust gaps in two-dimensional antiferromagnets via additional spin-1/2 probes},
  author={A. M. Ferreira and J. M. Viana Parente Lopes and J. M. B. Lopes dos Santos},
  journal={Physical Review A},
We study the capacity of antiferromagnetic lattices of varying geometries to entangle two additional spin-1/2 probes. Analytical modeling of the quantum Monte Carlo data shows the appearance of a robust gap, allowing a description of entanglement in terms of probe-only states, even in cases where the coupling to the probes is larger than the gap of the spin lattice and cannot be treated perturbatively. We find a considerable enhancement of the temperature at which probe entanglement disappears… 
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