Physics – Condensed Matter – Disordered Systems and Neural Networks
Scientific paper
2001-07-13
Phys. Rev. B 64, 180404 (2001)
Physics
Condensed Matter
Disordered Systems and Neural Networks
4 pages, 4 figures, 1 table, revtex
Scientific paper
10.1103/PhysRevB.64.180404
Exact ground states of two-dimensional Ising spin glasses with Gaussian and bimodal (+- J) distributions of the disorder are calculated using a ``matching'' algorithm, which allows large system sizes of up to N=480^2 spins to be investigated. We study domain walls induced by two rather different types of boundary-condition changes, and, in each case, analyze the system-size dependence of an appropriately defined ``defect energy'', which we denote by DE. For Gaussian disorder, we find a power-law behavior DE ~ L^\theta, with \theta=-0.266(2) and \theta=-0.282(2) for the two types of boundary condition changes. These results are in reasonable agreement with each other, allowing for small systematic effects. They also agree well with earlier work on smaller sizes. The negative value indicates that two dimensions is below the lower critical dimension d_c. For the +-J model, we obtain a different result, namely the domain-wall energy saturates at a nonzero value for L\to \infty, so \theta = 0, indicating that the lower critical dimension for the +-J model exactly d_c=2.
Hartmann Alexander K.
Young Patrick A.
No associations
LandOfFree
Lower Critical Dimension of Ising Spin Glasses does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Lower Critical Dimension of Ising Spin Glasses, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Lower Critical Dimension of Ising Spin Glasses will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-141030