J. Lukic, A. Galluccio, E. Marinari, Olivier C. Martin, G. Rinaldi
Published 2003-09-09, updated 2004-02-02Version 3
We compute the exact partition function of 2d Ising spin glasses with binary couplings. In these systems, the ground state is highly degenerate and is separated from the first excited state by a gap of size 4J. Nevertheless, we find that the low temperature specific heat density scales as exp(-2J/T), corresponding to an ``effective'' gap of size 2J; in addition, an associated cross-over length scale grows as exp(J/T). We justify these scalings via the degeneracy of the low-lying excitations and by the way low energy domain walls proliferate in this model.
Journal: Physical Review Letters 92 (2004) 117202
Zero and low temperature behavior of the two-dimensional $\pm J$ Ising spin glass
Instability of the ferromagnetic phase under random fields in an Ising spin glass with correlated disorder
Anomalous distribution of magnetization in an Ising spin glass with correlated disorder
