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arXiv · 1507.04954

First-order commensurate-incommensurate magnetic phase transition in the coupled FM spin-1/2 two-leg ladders

J. Jahangiri·H. Hadipour·S. Mahdavifar·S. Farjami Shayesteh
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Abstract

We consider the spin-1/2 two-leg ladders with ferromagnetic (FM) interactions along legs and rungs. Using the stochastic series expansion QMC method, we study the low-temperature magnetic behavior of the system. An isolated spin-1/2 FM two-leg ladder is in the gapped saturated FM phase at zero temperature. As soon as the spin-1/2 FM two-leg ladders are connected with antiferromagnetic (AFM) inter-ladder interaction, a first-order commensurate-incommensurate quantum phase transition occurs in the ground state magnetic phase diagram. In fact a jump in the magnetization curve is observed. We found that, coupled spin-1/2 FM two-leg ladders are in a nonmagnetic phase at zero temperature. Applying a magnetic field, the ground state of coupled spin-1/2 FM two-leg ladders remains in the nonmagnetic phase up to a quantum saturate critical field.

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J. Jahangiri, H. Hadipour, S. Mahdavifar, S. Farjami Shayesteh. 2015-07-17. First-order commensurate-incommensurate magnetic phase transition in the coupled FM spin-1/2 two-leg ladders. https://doi.org/10.1016/j.physb.2015.07.012

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