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Entanglement in a first order quantum phase transition

J. Vidal·R. Mosseri·J. Dukelsky
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Abstract

The phase diagram of spins 1/2 embedded in a magnetic field mutually interacting antiferromagnetically is determined. Contrary to the ferromagnetic case where a second order quantum phase transition occurs, a first order transition is obtained at zero field. The spectrum is computed for a large number of spins and allows one to study the ground state entanglement properties which displays a jump of its concurrence at the critical point.

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J. Vidal, R. Mosseri, J. Dukelsky. 2003-12-04. Entanglement in a first order quantum phase transition. https://doi.org/10.1103/physreva.69.054101

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