Date of Original Version
We investigate dynamic correlation functions for a pair of exchange‐coupled classical spins with biaxial exchange and/or single‐site anisotropy. This represents a Hamiltonian system with two degrees of freedom for which we have previously established the integrability criteria. We discuss the impact of (non‐)integrability on the autocorrelation functions and their spectral properties. We point out the role of long‐time anomalies caused by low‐flux cantori, which dominate the convergence properties of time averages and determine the long‐time asymptotic behavior of autocorrelation functions in nonintegrable cases.
Niraj Srivastava, Christoper Kaufman and Gerhard Müller. Chaos in spin clusters: correlation functions and spectral properties. J. Appl. Phys. 63 (1988), 4154-4156.
Available at: http://dx.doi.org/10.1063/1.340524