Ground states, magnetization plateaus and bipartite entanglement of frustrated spin-1/2 Ising-Heisenberg and Heisenberg triangular tubes

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:417

Article

Alecio, Raphael C.¹  Lyra, Marcelo L.¹  Strecka, Jozef² 

[1] Univ Fed Alagoas, Inst Fis, BR-57072970 Maceio, AL, Brazil

[2] Safarik Univ, Fac Sci, Dept Theoret Phys & Astrophys, Pk Angelinum 9, Kosice 04001, Slovakia

关键词: Spin tube;    Geometric frustration;    Magnetization plateau;    Quantum entanglement;   

DOI  :  10.1016/j.jmmm.2016.05.081

来源: Elsevier

【 摘 要 】

The ground-state phase diagram, magnetization process and bipartite entanglement of the frustrated spin-1/2 Ising-Heisenberg and Heisenberg triangular tube (three-leg ladder) are investigated in a non-zero external magnetic field. The exact ground-state phase diagram of the spin-1/2 Ising-Heisenberg tube with Heisenberg intra-rung and Ising inter-rung couplings consists of six distinct gapped phases, which manifest themselves in a magnetization curve as intermediate plateaus at zero, one-third and two-thirds of the saturation magnetization. Four out of six available ground states exhibit quantum entanglement between two spins from the same triangular unit evidenced by a non-zero concurrence. Density-matrix renormalization group calculations are used in order to construct the ground-state phase diagram of the analogous but purely quantum spin-1/2 Heisenberg tube with Heisenberg intra- and inter-rung couplings, which consists of four gapped and three gapless phases. The Heisenberg tube shows a continuous change of the magnetization instead of a plateau at zero magnetization, while the intermediate one-third and two-thirds plateaus may be present or not in the zero-temperature magnetization curve. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

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