# Entanglement witnesses in spin models

@article{Tth2005EntanglementWI, title={Entanglement witnesses in spin models}, author={G{\'e}za T{\'o}th}, journal={Physical Review A}, year={2005}, volume={71}, pages={010301} }

We construct entanglement witnesses using fundamental quantum operators of spin models which contain two-particle interactions and have a certain symmetry. By choosing the Hamiltonian as such an operator, our method can be used for detecting entanglement by energy measurement. We apply this method to the Heisenberg model in a cubic lattice with a magnetic field, the XY model, and other familiar spin systems. Our method provides a temperature bound for separable states for systems in thermal…

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