EXACT SPECTRA, SPIN SUSCEPTIBILITIES, AND ORDER-PARAMETER OF THE QUANTUM HEISENBERG-ANTIFERROMAGNET ON THE TRIANGULAR LATTICE

Article

关键词: GROUND-STATE PROPERTIES;    RESONATING-VALENCE-BOND;    SQUARE LATTICE;    FINITE-SIZE;    NEEL ORDER;    FRUSTRATED ANTIFERROMAGNETS;    STAGGERED MAGNETIZATION;    TEMPERATURE PROPERTIES;    SYMMETRY-BREAKING;    WAVE-FUNCTIONS;   

DOI  :  10.1103/PhysRevB.50.10048

来源: SCIE

【 摘 要 】

Exact spectra of periodic samples are computed up to N = 36, Evidence of an extensive set of low-lying levels, lower than the softest magnons, is exhibited. These low-lying quantum states are degenerated in the thermodynamic limit; their symmetries and dynamics as well as their finite-size scaling are strong arguments in favor of Neel order. It is shown that the Neel order parameter agrees with first-order spin-wave calculations. A simple explanation of the low-energy dynamics is given as well as the numerical determinations of the energies, order parameter, and spin susceptibilities of the studied samples. It is shown how suitable boundary conditions, which do not frustrate Neel order, allow the study of samples with N = 3p + 1 spins. A thorough study of these situations is done in parallel with the more conventional case N = 3p.

【 授权许可】

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