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Memory in nanomagnetic systems: Superparamagnetism versus Spinglass behavior

Malay Bandyopadhyay·Sushanta Dattagupta
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Abstract

The slow dynamics and concomitant memory (aging) effects seen in nanomagnetic systems are analyzed on the basis of two separate paradigms : superparamagnets and spinglasses. It is argued that in a large class of aging phenomena it suffices to invoke superparamagnetic relaxation of individual single domain particles but with a distribution of their sizes. Cases in which interactions and randomness are important in view of distinctive experimental signatures, are also discussed.

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Malay Bandyopadhyay, Sushanta Dattagupta. 2006-06-09. Memory in nanomagnetic systems: Superparamagnetism versus Spinglass behavior. https://doi.org/10.1103/physrevb.74.214410

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