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arXiv · 1508.00723

Phase diagram of a frustrated asymmetric ferromagnetic spin ladder

Lihua Pan·Depeng Zhang·Hsiang-Hsuan Hung·Yong-Jun Liu
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Abstract

We perform a systematic investigation on the ground state of an asymmetric two-leg spin ladder (where exchange couplings of the legs are unequal) with ferromagnetic (FM) nearest-neighbor interaction and diagonal anti-ferromagnetic frustration using the Density Matrix Renormalization Group (DMRG) method. When the ladder is strongly asymmetric with moderate frustration, a magnetic canted state is observed between a FM state and a singlet dimerized state. The phase boundaries are dependent on the asymmetric strength $\alpha_{a}$. On the other hand, when the asymmetric strength is intermediate, a so-called spin-stripe state (spins align parallel on same legs, but antiparallel on rungs) is discovered, and the system experiences a first-order phase transition from the FM state to the spin-stripe state upon increasing frustration. We present numerical evidence to interpret the phase diagram in terms of frustration and the asymmetric strength.

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Lihua Pan, Depeng Zhang, Hsiang-Hsuan Hung, Yong-Jun Liu. 2015-08-04. Phase diagram of a frustrated asymmetric ferromagnetic spin ladder. https://doi.org/10.1140/epjb%2Fe2017-70716-5

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