Finite-size scaling in systems with long-range interaction
Hassan Chamati
Abstract
The finite-size critical properties of the O(n) vector ϕ 4 model, with longrange interaction decaying algebraically with the interparticle distance r like r −d−σ, are investigated. The system is confined to a finite geometry subject to periodic boundary condition. Special attention is paid to the finite-size correction to the bulk susceptibility above the critical temperature Tc. We show that this correction has a power-law nature in the case of pure long-range interaction i.e. 0 < σ < 2 and it turns out to be exponential in case of shortrange interaction i.e. σ = 2. The results are valid for arbitrary dimension d, between the lower (d< = σ) and the upper (d> = 2σ) critical dimensions.