Inhaltszusammenfassung

We investigate the phase structure of the random-field Ising model with a bimodal random-field distribution. our aim is to test for the possibility of an equilibrium spin-glass phase, and for replica symmetry breaking (rsb) within such a phase. we study a low-temperature region where the spin-glass phase is thought to occur, but which has received little numerical study to date. we use the exchange monte carlo technique to acquire equilibrium information about the model. in particular the p(q...We investigate the phase structure of the random-field Ising model with a bimodal random-field distribution. our aim is to test for the possibility of an equilibrium spin-glass phase, and for replica symmetry breaking (rsb) within such a phase. we study a low-temperature region where the spin-glass phase is thought to occur, but which has received little numerical study to date. we use the exchange monte carlo technique to acquire equilibrium information about the model. in particular the p(q) distribution and the spectrum of eigenvalues of the spin-spin correlation matrix (which tests for the presence of rsb). our studies span the range in parameter space from the ferromagnetic to the paramagnetic phase. we find, however, no convincing evidence for any equilibrium glass phase, with or without rsb, between these two phases. instead we find evidence {[}principally from the p(q) distribution] that there are only two phases at this low temperature, with a discontinuity in the magnetization at the transition like that seen at other temperatures.» weiterlesen» einklappen

Autoren

Klassifikation

DFG Fachgebiet:
3.17 - Theoretische Chemie

DDC Sachgruppe:
Physik