Thermal entanglement in a two-qubit Ising chain subjected to Dzialoshinski-Moriya interaction

Thermal entanglement of a two-qubit Ising chain subjected to an external magnetic field and Dzialoshinski-Moriya (DM) interaction is examined. The effect of magnetic field, strength of DM interaction and temperature are analyzed by adopting negativity of partial transpose as the measure of entanglement. It is shown that when the DM interaction along the Ising axis is considerable, thermal entanglement can be sustained for higher temperature. The usefulness of longitudinal DM interaction over the one that is perpendicular to the Ising axis, in the manipulation and control of entanglement at a feasible temperature, is illustrated.