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The fate of spinons in spontaneously dimerised spin-1/2 ladders

Dave Allen·Fabian H. L. Essler·Alexander A. Nersesyan
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Abstract

We study a weakly coupled, frustrated two-leg spin-1/2 Heisenberg ladder. For vanishing coupling between the chains, elementary excitations are deconfined, gapless spin-1/2 objects called spinons. We investigate the fate of spinons for the case of a weak interchain interaction. We show that despite a drastic change in ground state, which becomes spontaneously dimerised, spinons survive as elementary excitations but acquire a spectral gap. We furthermore determine the exact dynamical structure factor for several values of momentum transfer.

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Dave Allen, Fabian H. L. Essler, Alexander A. Nersesyan. 2000-02-21. The fate of spinons in spontaneously dimerised spin-1/2 ladders. https://doi.org/10.1103/physrevb.61.8871

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