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Bound states of magnons in the S=1/2 quantum spin ladder

O. P. Sushkov·V. N. Kotov
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Abstract

We study the excitation spectrum of the two-leg antiferromagnetic S=1/2 Heisenberg ladder. Our approach is based on the description of the excitations as triplets above a strong-coupling singlet ground state. The quasiparticle spectrum is calculated by treating the excitations as a dilute Bose gas with infinite on-site repulsion. We find singlet (S=0) and triplet (S=1) two-particle bound states of the elementary triplets. We argue that bound states generally exist in any dimerized quantum spin model.

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BibTeXRIS

O. P. Sushkov, V. N. Kotov. 1998-03-14. Bound states of magnons in the S=1/2 quantum spin ladder. https://doi.org/10.1103/physrevlett.81.1941

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