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Incommensurate spin correlations in Heisenberg spin-1/2 zig-zag ladders

Alexander A. Nersesyan·Alexander O. Gogolin·Fabian H. L. Essler
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Abstract

We develop a low-energy effective theory for spin-1/2 frustrated two-leg Heisenberg spin ladders. We obtain a new type of interchain coupling that breaks parity symmetry. In the presence of an XXZ-type anisotropy, this interaction gives rise to a novel ground state, characterized by incommensurate correlations. In the case of a single ladder, this state corresponds to a spin nematic phase. For a frustrated quasi-one-dimensional system of infinitely many weakly coupled chains, this state develops true three dimensional spiral order. We apply our theory to recent neutron scattering experiments on $Cs_2CuCl_4$.

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Alexander A. Nersesyan, Alexander O. Gogolin, Fabian H. L. Essler. 1998-04-01. Incommensurate spin correlations in Heisenberg spin-1/2 zig-zag ladders. https://doi.org/10.1103/physrevlett.81.910

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