arXiv:cond-mat/9803290

Low-Lying Energy Properties of a Frustrated Antiferromagnetic Spin-$\frac 1 2$ Ladder

Xiaoqun Wang

Published Mar 24, 1998• 0 citations

Abstract

Using the Density Matrix Renormalization Group method, we determined the phase diagram of a frustrated antiferromagnetic spin-$\frac 1 2$ ladder at zero temperature. Two spin-gapped phases, the Haldane phase and the singlet phase, are identified. A phase transition between the two phases occurs at any non-zero value of frustration coupling $J_{\times}$. On the phase boundary, the spin gap vanishes for sufficiently small $J_{\times}$. Crossing this non-gapped line, the transition is of second order, while of first order for larger $J_{\times}$. Striking frustration effects are predicted for ladder materials.

DOI: 10.48550/arxiv.cond-mat/9803290

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arXiv:cond-mat/9803290

Low-Lying Energy Properties of a Frustrated Antiferromagnetic Spin- $\frac 1 2$ LadderLow-Lying Energy Properties of a Frustrated Antiferromagnetic Spin-$\frac 1 2$ Ladder

Xiaoqun Wang

Published Mar 24, 1998• 0 citations

arXiv HTML PDF

Abstract

Using the Density Matrix Renormalization Group method, we determined the phase diagram of a frustrated antiferromagnetic spin-

\frac 1 2

ladder at zero temperature. Two spin-gapped phases, the Haldane phase and the singlet phase, are identified. A phase transition between the two phases occurs at any non-zero value of frustration coupling

J_{\times}

. On the phase boundary, the spin gap vanishes for sufficiently small

J_{\times}

. Crossing this non-gapped line, the transition is of second order, while of first order for larger

J_{\times}

. Striking frustration effects are predicted for ladder materials.

DOI: 10.48550/arxiv.cond-mat/9803290

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Physical review. B, Condensed matterNov 15, 200211 citations

Low-Lying Energy Properties of a Frustrated Antiferromagnetic Spin-

\frac 1 2

Ladder

Using the Density Matrix Renormalization Group method, we determined the phase diagram of a frustrated antiferromagnetic spin-

\frac 1 2

J_{\times}

. On the phase boundary, the spin gap vanishes for sufficiently small

J_{\times}

. Crossing this non-gapped line, the transition is of second order, while of first order for larger

J_{\times}

. Striking frustration effects are predicted for ladder materials.

c=2.

The critical value of ${J}_{\ifmmode\times\else\texttimes\fi{}}$ is insensitive to the number of legs in the ladder, suggesting that a quantum phase transition may occur at ${J}_{\ifmmode\times\else\texttimes\fi{}}=0.6$ for the isotropic spin-1/2 antiferromagnetic Heisenberg model on the square lattice.