Ren Jie, Liu Guang-Hua, You Wen-Long
Department of Physics and Jiangsu Laboratory of Advanced Functional Material, Changshu Institute of Technology, Changshu 215500, People's Republic of China.
J Phys Condens Matter. 2015 Mar 18;27(10):105602. doi: 10.1088/0953-8984/27/10/105602. Epub 2015 Feb 23.
We study the fidelity susceptibility in an antiferromagnetic spin-1 XXZ chain numerically. By using the density-matrix renormalization group method, the effects of the alternating single-site anisotropy D on fidelity susceptibility are investigated. Its relation with the quantum phase transition is analyzed. It is found that the quantum phase transition from the Haldane spin liquid to periodic Néel spin solid can be well characterized by the fidelity. Finite size scaling of fidelity susceptibility shows a power-law divergence at criticality, which indicates the quantum phase transition is of second order. The results are confirmed by the second derivative of the ground-state energy. We also study the relationship between the entanglement entropy, the Schmidt gap and quantum phase transitions. Conclusions drawn from these quantum information observables agree well with each other.
我们通过数值方法研究反铁磁自旋-1 XXZ链中的保真度磁化率。利用密度矩阵重整化群方法,研究了交替单格点各向异性D对保真度磁化率的影响。分析了其与量子相变的关系。发现从霍尔丹自旋液体到周期性奈尔自旋固体的量子相变可以通过保真度很好地表征。保真度磁化率的有限尺寸标度在临界点呈现幂律发散,这表明量子相变是二级的。基态能量的二阶导数证实了这些结果。我们还研究了纠缠熵、施密特间隙与量子相变之间的关系。从这些量子信息可观测量得出的结论相互吻合得很好。