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Ferrimagnetic mixed-spin ladders in weak and strong coupling limits

D. N. Aristov·M. N. Kiselev
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Abstract

We study two similar spin ladder systems with the ferromagnetic leg coupling. First model includes two sorts of spins, s= 1/2 and s= 1, and the second model comprises only s=1/2 legs coupled by a "triangular" rung exchange. The antiferromagnetic (AF) rung coupling destroys the long-range order and eventually makes the systems equivalent to the AF s=1/2 Heisenberg chain. We investigate the situation by different methods in weak and strong rung coupling limits. Particularly we compare the spin-wave theory and the bosonization method in the weak coupling regime of the second model. We analyze the spectra and correlations, and discuss the order parameter of these ladder systems.

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D. N. Aristov, M. N. Kiselev. 2004-10-13. Ferrimagnetic mixed-spin ladders in weak and strong coupling limits. https://doi.org/10.1103/physrevb.70.224402

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