We have studied the barocaloric effect (BCE) in the geometrically frustrated antiferromagnet Mn3NiN across the N\'{e}el transition temperature. Experimentally we find a larger barocaloric entropy change by a factor of 1.6 than that recently discovered in the isostructural antiperovskite Mn3GaN despite greater magnetovolume coupling in the latter. By fitting experimental data to theory we show that the larger BCE of Mn3NiN originates from multi-site exchange interactions amongst the local Mn magnetic moments and their coupling with itinerant electron spins. Using this framework, we discuss the route to maximise the BCE in the wider Mn3AN family.
Cite
@article{arxiv.1806.02092,
title = {Multi-site exchange enhanced barocaloric response in Mn$_{3}$NiN},
author = {David Boldrin and Eduardo Mendive-Tapia and Jan Zemen and Julie B. Staunton and Thomas Hansen and Araceli Aznar and Josep-Lluís Tamarit and Maria Barrio and Pol Lloveras and Jiyeob Kim and Xavier Moya and Lesley F. Cohen},
journal= {arXiv preprint arXiv:1806.02092},
year = {2018}
}