Communications in Theoretical Physics
Quantum and Classical Correlations in Isotropic XY Chain with Three-Site Interaction
Ben‐Qiong Liu, Bin Shao, Jian Zou
Abstract
The quantum phase transition in the isotropic XY chain with three-site interaction has been studied by calculating the quantum discord, classical 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.