The Yang-Lee edge singularity studied by a four-level quantum renormalization-group blocking method
نویسندگان
چکیده
2014 A quantum renormalization-group technique is applied to the one-dimensional transverse field Ising model in a complex longitudinal field. The Yang-Lee edge singularity is analysed in this model in view of its analogy with the 2d classical Ising model. Previous two-level calculations are improved by retaining four levels in the blocking procedure. A more precise edge exponent 03C3 is found in agreement with the infinite block extrapolation of the two-level calculation, but still larger in absolute value than the latest series analysis results. The occurrence of oscillations in the real part of the magnetization appears to be an artifact of the real-space method, which introduces finite size effects. J. Physique 42 (1981) 1075-1080 AOÛT 1981,
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