Frustrated magnetism and caloric effects in Mn-based antiperovskite nitrides: Ab initio theoryShow others and affiliations
2017 (English)In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 95, no 18, article id 184438Article in journal (Refereed) Published
Abstract [en]
We model changes of magnetic ordering in Mn-based antiperovskite nitrides driven by biaxial lattice strain at zero and at finite temperature. We employ a noncollinear spin-polarized density functional theory to compare the response of the geometrically frustrated exchange interactions to a tetragonal symmetry breaking (the so called piezomagnetic effect) across a range of Mn(3)AN (A = Rh, Pd, Ag, Co, Ni, Zn, Ga, In, Sn) at zero temperature. Building on the robustness of the effect we focus onMn(3)GaN and extend our study to finite temperature using the disordered local moment (DLM) first-principles electronic structure theory to model the interplay between the ordering of Mn magnetic moments and itinerant electron states. We discover a rich temperature-strain magnetic phase diagram with two previously unreported phases stabilized by strains larger than 0.75% and with transition temperatures strongly dependent on strain. We propose an elastocaloric cooling cycle crossing two of the available phase transitions to achieve simultaneously a large isothermal entropy change (due to the first-order transition) and a large adiabatic temperature change (due to the second-order transition).
Place, publisher, year, edition, pages
AMER PHYSICAL SOC , 2017. Vol. 95, no 18, article id 184438
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:uu:diva-335760DOI: 10.1103/PhysRevB.95.184438ISI: 000411500800004OAI: oai:DiVA.org:uu-335760DiVA, id: diva2:1163979
Funder
EU, FP7, Seventh Framework Programme, 3107482017-12-082017-12-082017-12-08Bibliographically approved