Numerical evidence for the spin-Peierls state in the frustrated quantum antiferromagnet

Article

关键词: HEISENBERG-ANTIFERROMAGNET;    FINITE-SIZE;    SQUARE LATTICE;    MODELS;    TRANSITION;    PHASE;   

DOI  :  10.1103/PhysRevB.53.2213

来源: SCIE

【 摘 要 】

We study the spin-g Heisenberg antiferromagnet with an antiferromagnetic J(3) (third-nearest-neighbor) interaction on a square lattice. We numerically diagonalize this ''J(1)-J(3)'' model on clusters up to 32 sites and search for ground-state properties as the frustration parameter J(3)/J(1) changes. For ''larger'' J(3)/J(1) we find enhancement of the incommensurate spin order, in agreement with various theoretical predictions. But for intermediate J(3)/J(1), the low-lying excitation energy spectrum suggests that this incommensurate order is short range. Analysis of the ground-state expectation of the order parameter and the symmetries of the first excited state suggest that the spin-Peierls state is the best candidate for the ground state of the J(1)-J(3) model in an intermediate J(3)/J(1) region.

【 授权许可】

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