Measurement-induced disturbance and thermal negativity in 1D optical lattice chain

We study the measurement-induced disturbance (MID) in a 1D optical lattice chain with nonlinear coupling. Special attention is paid to the difference between the thermal entanglement and MID when considering the influences of the linear coupling constant, nonlinear coupling constant and external magnetic field. It is shown that MID is more robust than thermal entanglement against temperature TT and external magnetic field BB, and MID may reveal more properties about quantum correlations of the system, which can be seen from the point of view that MID can be nonzero when there is no thermal entanglement and MID can detect the critical point of quantum phase transition at finite temperature.

► The nonlinear coupling constant can strengthen the quantum correlation. ► MID is more robust than entanglement against temperature and magnetic field. ► MID exhibits more information about quantum correlation than entanglement. ► MID can detect the critical point of quantum phase transition at finite temperature.