Ab initio study of electronic and magnetic properties of FeRh(001), FeRh(110) and FeRh(111) ultrathin films

JIMÉNEZ, M. JULIA; SCHVVAL, ANA BELÉN; CABEZA, GABRIELA F.

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

ELSEVIER SCIENCE BV

Año: 2021 vol. 526

0304-8853

In this work, the structural, magnetic and energetic properties of ultrathin FeRhfilms grown in different crystallographic planes,namely (100), (110) and (111), areinvestigated by using density functional theory calculations. Different thicknesses,atom terminations and magnetic phases (FM and AFM) have been considered. Theconclusions differ depending on the direction of growth. In general, values regardingsurface energy follow the relationship s110 < s001 < s111 where they grow withincreasing thickness, the Rh-terminated surfaces also have higher values withrespect to the Fe-terminated ones. Regarding stability, FeRh(001) and FeRh(110)surfaces have similar energy per atom values and are favored with respect to FeRh(111).In relation to the study of the normal relaxations to surfaces from the thirteensystems, it could be concluded that except for the FeRh(111) surface where contractionsbetween the layers are noticed regardless of termination and magneticconfiguration, the other ones show relaxations. Theimportance of the magnetic order in the films energy stabilization is alsoanalyzed. In summary, it could be said that in most cases Rh-terminated filmspresent unstable and even unpredictable behaviors depending on the number oflayers. This suggests that Rh is important in improving some properties, but onlywhen the number of layers is less than that of Fe. That is, the filmconstruction will depend on the specific interest of the particular applicationto be used in.