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Spin-liquid versus dimerized ground states in a frustrated Heisenberg antiferromagnet

Luca Capriotti·Douglas J. Scalapino·Steven R. White
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Abstract

We present a Density Matrix Renormalization Group (DMRG) study of the ground-state properties of spin-1/2 frustrated $J_1-J_3$ Heisenberg $n_l$-leg ladders (with $n_l$ up to 8). For strong frustration ($J_3/J_1\simeq 0.5$), both even- and odd-leg ladders display a finite gap to spin excitations, which we argue remains finite in the two-dimensional limit. In this regime, on odd-leg ladders the ground state is spontaneously dimerized, in agreement with the Lieb-Schultz-Mattis prediction, while on even-leg ladders the dimer correlations decay exponentially. The magnitude of the dimer order parameter decreases as the number of legs increases, consistent with a two-dimensional spin-liquid ground state.

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Luca Capriotti, Douglas J. Scalapino, Steven R. White. 2004-04-05. Spin-liquid versus dimerized ground states in a frustrated Heisenberg antiferromagnet. https://doi.org/10.1103/physrevlett.93.177004

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