Interacting nanoparticle systems spin glasses

III. STRONGLY INTERACTING NANOPARTICLE SYSTEMS— SPIN-GLASS-LIKE BEHAVIOR... 

III. Strongly Interacting Nanoparticle Systems-A. Spin Glasses... 

The susceptibility described above is also called the linear susceptibility because, in a Taylor expansion of M(H) about the applied field value, it is the coefficient of the term that is linear in H. In this way, higher order susceptibilities can be defined and measured. The higher order (non-linear) susceptibilities can provide information that is not contained in the linear term alone. This information has turned out to be vital in systems of interacting clusters or particles, such as ensembles of magnetic nanoparticles, canonical spin glasses and cluster spin glass systems (see below). 

SUPERPARAMAGNETISM AND SPIN GLASS DYNAMICS OF INTERACTING MAGNETIC NANOPARTICLE SYSTEMS... 

This nanoparticle sample exhibits strong anisotropy, due to the uniaxial anisotropy of the individual particles and the anisotropic dipolar interaction. The relative timescales (f/xm) of the experiments on nanoparticle systems are shorter than for conventional spin glasses, due to the larger microscopic flip time. The nonequilibrium phenomena observed here are indeed rather similar to those observed in numerical simulations on the Ising EA model [125,126], which are made on much shorter time (length) scales than experiments on ordinary spin glasses [127]. 

Superparamagnetism and Spin Glass Dynamics of Interacting Magnetic Nanoparticle Systems By Petra E. Jonsson... 

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