High temperature correlation functions: universality, extraction of exchange interactions, divergent correlation lengths and generalized Debye length scales

Abstract

We derive a universal form for the correlation function of general n component systems in the limit of high temperatures or weak coupling. This enables the extraction of effective microscopic interactions from measured high temperature correlation functions. We find that in systems with long range interactions, there exist diverging correlation lengths with amplitudes that tend to zero in the high temperature limit. For general systems with disparate long range interactions, we introduce the notion of generalized Debye length (and time) scales and further relate it to the divergence of the largest correlation length in the high temperature (or weak coupling) limit.

11 pages

References in corpus (3)

• Ising models with long-range dipolar and short-range ferromagnetic interactions
• Striped phases in two dimensional dipole systems
• Stripe width and non-local domain walls in the two-dimensional Dipolar Frustrated Ising Ferromagnet

Cited by in corpus (8)

• Effective and exact holographies from symmetries and dualities
• Modulation and correlations lengths in systems with competing interactions
• Universality of modulation length (and time) exponents
• Inferring entropy from structure
• Macroscopic Length Correlations in Non-Equilibrium Systems and Their Possible Realizatons
• Compass and Kitaev models -- Theory and Physical Motivations
• Resolving entropy contributions in nonequilibrium transitions
• Direct Boltzmann inversion method from particle configurations at arbitrary state points