Abstract
A systematic approach to the calculations of the non-perturbative contributionsto the free energy in the ferromagnetic phase of the random field Ising modelis developed. It is demonstrated that such contributions appear due toinstanton-like excitations localized in space, which exist only in dimensionsD≤3.It is shown that away from the critical region such instanton solutions are described by the set ofthe mean-field saddle-point equations for the replica vector order parameter, and these equationscan be formally reduced to the only saddle-point equation of the pure system in dimensions(D−2). In themarginal case, D = 3, the corresponding non-analytic contribution is computed explicitly. The nature of thephase transition in the three-dimensional random field Ising model is discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of Statistical Mechanics: Theory and Experiment
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
