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Random Exchange Disorder in the Spin-1/2 XXZ Chain

Stephan Haas·Jose Riera·Elbio Dagotto
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Abstract

The one-dimensional XXZ model is studied in the presence of disorder in the Heisenberg Exchange Integral. Recent predictions obtained from renormalization group calculations are investigated numerically using a Lanczos algorithm on chains of up to 18 sites. It is found that in the presence of strong X-Y-symmetric random exchange couplings, a ``random singlet'' phase with quasi-long-range order in the spin-spin correlations persists. As the planar anisotropy is varied, the full zero-temperature phase diagram is obtained and compared with predictions of Doty and Fisher [Phys. Rev. B {\bf 45 }, 2167 (1992)].

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Stephan Haas, Jose Riera, Elbio Dagotto. 1993-08-18. Random Exchange Disorder in the Spin-1/2 XXZ Chain. https://doi.org/10.1103/physrevb.48.13174

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