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Paradoxical Magnetic Cooling in a Structural Transition Model

Peter Borrmann·Heinrich Stamerjohanns·Eberhard R. Hilf·David Tomanek
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Abstract

In contrast to the experimentally widely used isentropic demagnetization process for cooling to ultra-low temperatures we examine a particular classical model system that does not cool, but rather heats up with isentropic demagnetization. This system consists of several magnetite particles in a colloidal suspension, and shows the uncommon behavior of disordering structurally while ordering magnetically in an increasing magnetic field. For a six-particle system, we report an uncommon structural transition from a ring to a chain as a function of magnetic field and temperature.

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Peter Borrmann, Heinrich Stamerjohanns, Eberhard R. Hilf, David Tomanek. 2001-02-02. Paradoxical Magnetic Cooling in a Structural Transition Model. https://doi.org/10.1007/s100510170356

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