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arXiv · 1105.0533

Ground state fidelity in bond-alternative Ising chains with Dzyaloshinskii-Moriya interactions

Bo Li·Sam Young Cho·Hong-Lei Wang·Bing-Quan Hu
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Abstract

A systematic analysis is performed for quantum phase transitions in a bond-alternative one-dimensional Ising model with a Dzyaloshinskii-Moriya (DM) interaction by using the fidelity of ground state wave functions based on the infinite matrix product states algorithm. For an antiferromagnetic phase, the fidelity per lattice site exhibits a bifurcation, which shows spontaneous symmetry breaking in the system. A critical DM interaction is inversely proportional to an alternating exchange coupling strength for a quantum phase transition. Further, a finite-entanglement scaling of von Neumann entropy with respect to truncation dimensions gives a central charge c = 0.5 at the critical point.

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Bo Li, Sam Young Cho, Hong-Lei Wang, Bing-Quan Hu. 2011-05-03. Ground state fidelity in bond-alternative Ising chains with Dzyaloshinskii-Moriya interactions. https://doi.org/10.1088/1751-8113/44/39/392002

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