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arXiv · 1205.0727

Magnetocaloric effect in spin-1/2 $XX$ chains with three-spin interactions

Myroslava Topilko·Taras Krokhmalskii·Oleg Derzhko·Vadim Ohanyan
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Abstract

We consider the exactly solvable spin-1/2 $XX$ chain with the three-spin interactions of the $XZX+YZY$ and $XZY-YZX$ types in an external (transverse) magnetic field. We calculate the entropy and examine the magnetocaloric effect for the quantum spin system. We discuss a relation between the cooling/heating efficiency and the ground-state phase diagram of the quantum spin model. We also compare ability to cool/heat in the vicinity of the quantum critical and triple points. Moreover, we examine the magnetocaloric effect for the spin-1/2 $XX$ chain with three-spin interactions in a random (Lorentzian) transverse magnetic field.

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Myroslava Topilko, Taras Krokhmalskii, Oleg Derzhko, Vadim Ohanyan. 2012-05-03. Magnetocaloric effect in spin-1/2 $XX$ chains with three-spin interactions. https://doi.org/10.1140/epjb/e2012-30359-8

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