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Eur. Phys. J. B 38, 83-91 (2004)
DOI: 10.1140/epjb/e2004-00102-5

Stiffness exponents for lattice spin glasses in dimensions $\mathsf{d=3,\ldots,6}$

S. Boettcher

Physics Department, Emory University, Atlanta, Georgia 30322, USA

sboettc@emory.edu

(Received 29 October 2003 / Published online 20 April 2004)

Abstract
The stiffness exponents in the glass phase for lattice spin glasses in dimensions $d=3,\ldots,6$ are determined. To this end, we consider bond-diluted lattices near the T=0 glass transition point p*. This transition for discrete bond distributions occurs just above the bond percolation point pc in each dimension. Numerics suggests that both points, pc and p*, seem to share the same 1/d-expansion, at least for several leading orders, each starting with 1/(2d). Hence, these lattice graphs have average connectivities of $\alpha=2dp\gtrsim1$ near p* and exact graph-reduction methods become very effective in eliminating recursively all spins of connectivity $\leq3$, allowing the treatment of lattices of lengths up to L=30 and with up to 105-106 spins. Using finite-size scaling, data for the defect energy width $\sigma(\Delta E)$ over a range of p>p* in each dimension can be combined to reach scaling regimes of about one decade in the scaling variable $L(p-p^*)^{\nu^*}$. Accordingly, unprecedented accuracy is obtained for the stiffness exponents compared to undiluted lattices ( p=1), where scaling is far more limited. Surprisingly, scaling corrections typically are more benign for diluted lattices. We find in $d=3,\ldots,6$ for the stiffness exponents y3=0.24(1), y4=0.61(2), y5=0.88(5), and y6=1.1(1).

PACS
05.50.+q - Lattice theory and statistics (Ising, Potts, etc.).
64.60.Cn - Order-disorder transformations; statistical mechanics of model systems.
75.10.Nr - Spin-glass and other random models.
02.60.Pn - Numerical optimization.

© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2004