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arXiv · 1903.01754

Magnetocaloric properties of frustrated tetrahedra-based spin nanoclusters

M. Mohylna·M. Žukovič
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Abstract

Magnetization, entropy and magnetocaloric properties of various geometrically frustrated tetrahedra-based Ising antiferromagnetic nanoclusters with corner-, edge-, and face-sharing topologies are studied by exact enumeration. It is found that the studied properties strongly depend on the nanocluster topology and can be very different from those of a single tetrahedron as well as the pyrochlore lattice formed by an infinite number of corner-sharing tetrahedra. From the magnetocaloric point of view an important difference from the latter two systems is the absence of the ground-state zero-magnetization plateau in most of the studied structures, which at low temperatures facilitates emergence of a giant magnetocaloric effect in a vanishing magnetic field in the adiabatic demagnetization process. Magnetic systems with such properties might be suitable candidates for technological application as efficient refrigerators to ultra-low temperatures.

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M. Mohylna, M. Žukovič. 2019-03-05. Magnetocaloric properties of frustrated tetrahedra-based spin nanoclusters. https://doi.org/10.1016/j.physleta.2019.05.015

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