Modern Physics Letters B
Quantum discord and quantum phase transition in the XXZ spin chain with three-site interaction
Jing Yang, Mei-Yan Cong, Yanxia Huang
Abstract
Pairwise quantum discord (QD) and entanglement of the three-qubit XXZ Heisenberg spin chain with two types of three-site interactions and an external magnetic field are investigated. Our study found that both entanglement and quantum discord could detect the quantum critical phenomena of this model. We were able to obtain a nonzero value of quantum discord even at high temperature with the increase of XZX[Formula: see text]YZY or XZY[Formula: see text]YZX three-site interaction, however, the cooperative effect of XZX[Formula: see text]YZY and XZY[Formula: see text]YZX interactions is more ideal. Furthermore, in contrast to XZY[Formula: see text]YZX and XZX[Formula: see text]YZY interactions, the cooperative effect of XZX[Formula: see text]YZY and XZY[Formula: see text]YZX three-site interactions is more efficient to enhance the maximum value of quantum discord. Likewise, the cooperative effect of XZX[Formula: see text]YZY and XZY[Formula: see text]YZX interactions is the most optimal to increase the range of magnetic field or anisotropy parameter where quantum discord maintains the maximum value.