ua nt - p h / 04 07 07 3 v 3 2 5 N ov 2 00 4 Thermal entanglement of spins in an inhomogeneous magnetic field
نویسندگان
چکیده
We study the effect of inhomogeneities in the magnetic field on the thermal entanglement of a two spin system. We show that in the ferromagnetic case a very small inhomogeneity is capable to produce large values of thermal entanglement. This shows that the absence of entanglement in the ferromagnetic Heisenberg system is highly unstable against inhomogeneoity of magnetic fields which is inevitably present in any solid state realization of qubits.
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