J. A. BlackmanJ. R. GonçalvesJ. PoulterUniversity of ReadingMahidol University2018-07-042018-07-041998-01-01Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics. Vol.58, No.2 (1998), 1502-15071063651X2-s2.0-0001328339https://repository.li.mahidol.ac.th/handle/20.500.14594/18430We develop an exact gauge-invariant method for studying the two-dimensional [Formula Presented] spin glass. It is applied to the case of an arbitrary concentration of [Formula Presented] positive and p negative bonds and is thus a generalization of the more commonly studied [Formula Presented] model. The ground-state properties are examined and in particular it is shown that the spin correlation exponent η remains constant over the range [Formula Presented] The value obtained is [Formula Presented] A wide range of values for η is quoted in the literature. We indicate possible reasons for the discrepancies and indicate that there are potential advantages in doing calculations at concentrations markedly lower than 50%. © 1998 The American Physical Society.Mahidol UniversityMathematicsPhysics and AstronomyArticleSCOPUS10.1103/PhysRevE.58.1502