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Density-Matrix Renormalization-Group Analysis of Quantum Critical Points: I. Quantum Spin Chains

Shan-Wen Tsai·J. B. Marston
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Abstract

We present a simple method, combining the density-matrix renormalization-group (DMRG) algorithm with finite-size scaling, which permits the study of critical behavior in quantum spin chains. Spin moments and dimerization are induced by boundary conditions at the chain ends and these exhibit power-law decay at critical points. Results are presented for the spin-1/2 Heisenberg antiferromagnet; an analytic calculation shows that logarithmic corrections to scaling can sometimes be avoided. We also examine the spin-1 chain at the critical point separating the Haldane gap and dimerized phases. Exponents for the dimer-dimer and the spin-spin correlation functions are consistent with results obtained from bosonization.

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Shan-Wen Tsai, J. B. Marston. 2000-06-06. Density-Matrix Renormalization-Group Analysis of Quantum Critical Points: I. Quantum Spin Chains. https://doi.org/10.1103/physrevb.62.5546

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