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arXiv · 1105.3527

Combined analytical and numerical approach to study magnetization plateaux in doped quasi-one-dimensional antiferromagnets

C. A. Lamas·S. Capponi·P. Pujol
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Abstract

We investigate the magnetic properties of quasi-one-dimensional quantum spin-S antiferromagnets. We use a combination of analytical and numerical techniques to study the presence of plateaux in the magnetization curve. The analytical technique consists in a path integral formulation in terms of coherent states. This technique can be extended to the presence of doping and has the advantage of a much better control for large spins than the usual bosonization technique. We discuss the appearance of doping-dependent plateaux in the magnetization curves for spin-S chains and ladders. The analytical results are complemented by a density matrix renormalization group (DMRG) study for a trimerized spin-1/2 and anisotropic spin-3/2 doped chains.

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C. A. Lamas, S. Capponi, P. Pujol. 2011-05-18. Combined analytical and numerical approach to study magnetization plateaux in doped quasi-one-dimensional antiferromagnets. https://doi.org/10.1103/physrevb.84.115125

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