Effect of the ground-state structure on order parameters in ± J Ising lattices

A. J. RAMIREZ-PASTOR; F. ROMÁ; F. NIETO; E. E. VOGEL

PHYSICA A - STATISTICAL AND THEORETICAL PHYSICS

Elsevier

Lugar: Amsterdam; Año: 2004 vol. 336 p. 454 - 460

0378-4371

The Edwards–Anderson site order parameter, q, or itsgeneralizations have been considered to study the partialspin-glass behavior of ±J Ising lattices. These parameters vanishif all 2 W ground states are taken into account, so an ergodicseparation must be done in order to emulate nature.Here,we followa recently proposed criterion to do ergodic separation in spinglasses.The method relies upon:(i)the complete knowledge of thephysical properties of the ground level and (ii)a new algorithm tocalculate the diluted lattice that remains after removing allbonds that frustrate in any of the ground states.With this newmethodology,reproducible values of the order parameters have beenobtained. Size effects and tendency towards the thermodynamiclimit are established.