Effects of inhomogeneous magnetic field and magnetic impurity on the quantum correlation of spin-1 system

Abstract

We investigate the effects of inhomogeneous magnetic field and magnetic impurity on the quantum correlation in spin-1 system by means of negativity and measurement-induced disturbance. Results show that the increase of the inhomogeneous magnetic field not only decreases entanglement, but also can induce the entanglement, and increases the value of critical nonlinear coupling Kc. The critical magnetic field for measurement-induced disturbance is higher than that for negativity, and the measurement-induced disturbance (MID) will not disappear with the decrease of nonlinear coupling |K|, so it can reveal all the properties of quantum correlation. Results also show that the effects of different magnetic impurity on MID are independent of each other. Under the magnetic impurity, the entanglement exists only if the couplings |J| are less than the nonlinear couplings |K|, while there will be the MID when the couplings |J| are greater than the nonlinear couplings |K|. It is just the minimum point for MID when |J| equals to |K|. Moreover, the size of the Chain will influence the quantum correlation also.