Random-exchange disorder in the spin-1/2 XXZ chain.
نویسندگان
چکیده
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 45 , 2167 (1992)]. PACS Indices: 64.10.Pf, 05.30.Jp, 05.70.Jk Typeset using REVTEX
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ورودعنوان ژورنال:
- Physical review. B, Condensed matter
دوره 48 17 شماره
صفحات -
تاریخ انتشار 1993