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Search for quantum dimer phases and transitions in a frustrated spin ladder

Hsiang-Hsuan Hung·Chang-De Gong·Yung-Chung Chen·Min-Fong Yang
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Abstract

A two-leg spin-1/2 ladder with diagonal interactions is investigated numerically. We focus our attention on the possibility of columnar dimer phase, which was recently predicted based on a reformulated bosonization theory. By using density matrix renormalization group technique and exact diagonalization method, we calculate columnar dimer order parameter, spin correlation on a rung, string order parameters, and scaled excitation gaps. Carefully using various finite-size scaling techniques, our results show no support for the existence of columnar dimer phase in the spin ladder under consideration.

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Hsiang-Hsuan Hung, Chang-De Gong, Yung-Chung Chen, Min-Fong Yang. 2006-05-30. Search for quantum dimer phases and transitions in a frustrated spin ladder. https://doi.org/10.1103/physrevb.73.224433

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