Adaptive Density-Matrix Renormalization-Group study of the disordered antiferromagnetic spin-1/2 Heisenberg chain

Alexander H. O. Wada; José A. Hoyos

doi:10.1103/physrevb.105.104205

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arXiv · 2112.10420

Adaptive Density-Matrix Renormalization-Group study of the disordered antiferromagnetic spin-1/2 Heisenberg chain

Alexander H. O. Wada·José A. Hoyos

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Abstract

Using the recently introduced adaptive density-matrix renormalization-group method, we study the many spin-spin correlations of the spin-$1/2$ antiferromagnetic Heisenberg chain with random coupling constants, namely, the mean value of the bulk and of the end-to-end correlations, the typical value of the bulk correlations, and the distribution of the bulk correlations. Our results are in striking agreement with the predictions of the strong-disorder renormalization group method. We do not find any hint of logarithmic corrections neither in the bulk average correlations, which were recently reported by Shu et al. [Phys. Rev. B 94,174442 (2016)], nor in the end-to-end average correlations. We report computed the existence of logarithmic correction on the end-to-end correlations of the clean chain. Finally, we have determined that the distribution of the bulk correlations, when properly rescaled by an associated Lyapunov exponent, is a narrow and universal (disorder-independent) probability function.

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Alexander H. O. Wada, José A. Hoyos. 2022-03-25. Adaptive Density-Matrix Renormalization-Group study of the disordered antiferromagnetic spin-1/2 Heisenberg chain. https://doi.org/10.1103/physrevb.105.104205

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