Scaling Theory of Antiferromagnetic Heisenberg Ladder Models
نویسندگان
چکیده
The S = 1/2 antiferromagnetic Heisenberg model on multi-leg ladders is investigated. Criticality of the ground-state transition is explored by means of finite-size scaling. The ladders with an even number of legs and those with an odd number of legs are distinguished clearly. In the former, the energy gap opens up as ∆E ∼ J⊥, where J⊥ is the strength of the antiferromagnetic inter-chain coupling. In the latter, the critical phase with the central charge c = 1 extends over the whole region of J⊥ > 0.
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