Application of RenormalizationGroup Techniques to Random Magnetic Systems.
Abstract
Secondorder phase transitions in pure, homogeneous systems and the renormalization group framework are reviewed. Quenched random magnetic systems are introduced and momentumspace methods and positionspace techniques as applied to quenched random magnets are outlined and compared. The randomly bonddilute twodimensional nearestneighbor Ising model on a square lattice is studied. Calculations give both thermal and magnetic exponents associated with the percolative fixed point. Differential recursion relations yield a phase diagram which is in quantitative agreement with all known results. Curves for the specific heat, percolation probability, and magnetization are displayed. The EdwardsAnderson model of a spin glass is examined as well as the spin1/2 Ising model with independently random nearestneighbor interactions in dimensionalities d = 2, 3, and 4.
 Publication:

Ph.D. Thesis
 Pub Date:
 February 1979
 Bibcode:
 1979PhDT.........5J
 Keywords:

 Physics: Condensed Matter;
 Ferromagnetism;
 Normalizing (Statistics);
 Phase Diagrams;
 SpinLattice Relaxation;
 Glass;
 Perturbation Theory;
 Phase Transformations;
 Thermodynamic Properties;
 SolidState Physics