Paradoxical magnetic cooling in a structural transition model
نویسندگان
چکیده
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. PACS. 05.70.Fh Phase transitions: general studies – 75.10.-b General theory and models of magnetic ordering – 75.50.Mm Magnetic liquids
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