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Ising-model description of the SU(2)_1 quantum critical point in a dimerized two-leg spin-1/2 ladder

Y. -J. Wang·A. A. Nersesyan
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Abstract

A nonperturbative analytical description of the SU(2)_1 quantum critical point in an explicitly dimerized two-leg spin-1/2 Heisenberg ladder is presented. It is shown that this criticality essentially coincides with that emerging in a weakly dimerized spin-1 chain with a small Haldane gap. The approach is based on the mapping onto an SO(3)-symmetric model of three strongly coupled quantum Ising chains. This mapping is used to establish the correspondence between all physical fields of the spin ladder and those characterizing the SU(2)_1 criticality at the infrared fixed point.

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Y. -J. Wang, A. A. Nersesyan. 2000-04-26. Ising-model description of the SU(2)_1 quantum critical point in a dimerized two-leg spin-1/2 ladder. https://doi.org/10.1016/s0550-3213(00)00305-9

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