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Magnetization plateaux and jumps in a class of frustrated ladders: A simple route to a complex behaviour

A. Honecker·F. Mila·M. Troyer
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Abstract

We study the occurrence of plateaux and jumps in the magnetization curves of a class of frustrated ladders for which the Hamiltonian can be written in terms of the total spin of a rung. We argue on the basis of exact diagonalization of finite clusters that the ground state energy as a function of magnetization can be obtained as the minimum - with Maxwell constructions if necessary - of the energies of a small set of spin chains with mixed spins. This allows us to predict with very elementary methods the existence of plateaux and jumps in the magnetization curves in a large parameter range, and to provide very accurate estimates of these magnetization curves from exact or DMRG results for the relevant spin chains.

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A. Honecker, F. Mila, M. Troyer. 2000-01-05. Magnetization plateaux and jumps in a class of frustrated ladders: A simple route to a complex behaviour. https://doi.org/10.1007/s100510051120

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