Particle-like behavior of defects near a defect line in 2D Ising model: Defect–antidefect pair production and interaction

Abstract

The aim of this work is to investigate Casimir effect in a system comprising of a defect line along with isolated defects (vacancies) in 2D Ising model. We have found out that the interaction energy has a decaying exponent with distance between defects. We are interested in an analogy between Casimir behavior of this defect structure and quantum field theory. The simplest deformation of a defect line (a defect’s position change) can be treated as defect–“antidefect” pair creation. Single defect is attracted to a defect line. By means of Monte Carlo simulation, the energy of pair creation and Casimir interaction potential are calculated. The interaction turned out that a Yukawa potential turns to the Coulomb’s one at phase transition point.