https://doi.org/10.1140/epjb/e2012-30936-9
Regular Article
Complex magnetic ordering as a driving mechanism of multifunctional properties of Heusler alloys from first principles*
1
Faculty of Physics and CENIDE, University of
Duisburg-Essen, 47048
Duisburg,
Germany
2
Department of Mechanical Engineering, Texas A&M
University, College
Station, 77843
Texas,
USA
3
National University of Science and Technology
‘MISIS’, 119049
Moscow,
Russia
4
Condensed Matter Physics Department, Chelyabinsk State
University, 454001
Chelyabinsk,
Russia
5
IMEM Department of Magnetic Materials, CNR,
Parco delle Scienze 37/a,
43010
Parma,
Italy
6
Dipartimento Chimica GIAF, Università di Parma,
43124
Parma,
Italy
7
Universidad del Pais Vasco, Departamento de Electricidad y
Electronica, P.O. Box
644, 48080
Bilbao,
Spain
8
Ikerbasque, Basque Foundation for Science,
48011
Bilbao,
Spain
a e-mail: entel@thp.uni-duisburg.de
Received:
12
October
2012
Received in final form:
12
December
2012
Published online:
20
February
2013
First-principles calculations are used to study the structural, electronic and magnetic properties of (Pd, Pt)-Mn-Ni-(Ga, In, Sn, Sb) alloys, which display multifunctional properties like the magnetic shape-memory, magnetocaloric and exchange bias effect. The ab initio calculations give a basic understanding of the underlying physics which is associated with the complex magnetic behavior arising from competing ferro- and antiferromagnetic interactions with increasing number of Mn excess atoms in the unit cell. This information allows to optimize, for example, the magnetocaloric effect by using the strong influence of compositional changes on the magnetic interactions. Thermodynamic properties can be calculated by using the ab initio magnetic exchange parameters in finite-temperature Monte Carlo simulations. We present guidelines of how to improve the functional properties. For Pt-Ni-Mn-Ga alloys, a shape memory effect with 14% strain can be achieved in an external magnetic field.
Key words: Topical issue: New trends in magnetism and magnetic materials. Guest editors: Francesca Casoli, Massimo Solzi and Paola Tiberto
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2013