摘要
The quantum phase transition in the isotropic XY chain with three-site interaction has been studied by calculating the quantum discord, classicai correlation, and concurrence measuring entanglement. It is found that the quantum discord is a better choice than concurrence to signal the presence of the quantum phase transition in this model, since that for next-nearest neighbor spins the derivative of the quantum discord still exhibits singularity at the critical point while there is no more entanglement.
基金
Supported by National Natural Science Foundation of China under Grant Nos. 11075013 and 10974016
