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Nonanalytic correlation length in Ising systems with one surface defect line

A. Hucht
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Abstract

A two-dimensional Ising system with ferromagnetic coupling and one defect line at distance L from the surface is solved exactly using Pfaffians. The system shows a singularity in the surface correlation length at a temperature T_s which is smaller than the transition temperature T_c of the bulk. Numerical studies using the transfer matrix technique suggest that this singularity is also present in an Ising system with two defect lines at distance L.

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A. Hucht. 2001-10-17. Nonanalytic correlation length in Ising systems with one surface defect line. https://doi.org/10.1016/0378-4371(92)90188-v

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