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

TL;DR

This paper investigates the magnetocaloric effect in exactly solvable spin-1/2 XX chains with three-spin interactions, analyzing entropy, cooling efficiency, and effects near quantum critical points, including in random magnetic fields.

Contribution

It provides an exact analysis of the magnetocaloric effect in XX chains with three-spin interactions, exploring phase diagram relations and effects in random fields.

Findings

Enhanced cooling near quantum critical points

Distinct behavior in random magnetic fields

Relation between ground-state phases and magnetocaloric efficiency

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.