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Spin and chiral orderings of frustrated quantum spin chains

M. Kaburagi·H. Kawamura·T. Hikihara
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Abstract

Ordering of frustrated S=1/2 and 1 XY and Heisenberg spin chains with the competing nearest- and next-nearest-neighbor antiferromagnetic couplings is studied by exact diagonalization and density-matrix renormalization-group methods. It is found that the S=1 XY chain exhibits both gapless and gapped `chiral' phases characterized by the spontaneous breaking of parity, in which the long-range order parameter is a chirality, $κ_i = S_i^xS_{i+1}^y-S_i^yS_{i+1}^x$, whereas the spin correlation decays either algebraically or exponentially. Such chiral phases are not realized in the S=1/2 XY chain nor in the Heisenberg chains.

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M. Kaburagi, H. Kawamura, T. Hikihara. 1999-08-26. Spin and chiral orderings of frustrated quantum spin chains. https://doi.org/10.1143/jpsj.68.3185

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