Frustrated quantum Heisenberg ferrimagnetic chains

Article

关键词: MATRIX RENORMALIZATION-GROUP;    LOW-TEMPERATURE PROPERTIES;    SPIN CHAIN;    STATES;    S=1;    ANTIFERROMAGNET;    TRANSITION;    SYSTEMS;    DIMERIZATION;    FERROMAGNET;   

DOI  :  10.1103/PhysRevB.58.14456

来源: SCIE

【 摘 要 】

We study the ground-state properties of weakly frustrated Heisenberg ferrimagnetic chains with nearest- and next-nearest-neighbor antiferromagnetic exchange interactions and two types of alternating sublattice spins S-1>S-2, using 1/S spin-wave expansions, density-matrix renormalization group, and exact diagonalization techniques. It is argued that the zero-point spin fluctuations completely destroy the classical commensurate in commensurate continuous transition. Instead, the long-range ferrimagnetic state disappears through a discontinuous transition to a singlet state at a larger value of the frustration parameter. In the ferrimagnetic phase we find a disorder point marking the onset of incommensurate real-space short-range spin-spin correlations. [S0163-1829(98)05042-5].

【 授权许可】

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