A Minimal tight-binding model for ferromagnetic canted bilayer manganites

• Published in: Scientific reports Vol. 4; no. 1; p. 7512
• Main Authors: Baublitz, M., Lane, C., Lin, Hsin, Hafiz, Hasnain, Markiewicz, R. S., Barbiellini, B., Sun, Z., Dessau, D. S., Bansil, A.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 19.12.2014; Nature Publishing Group
• Subjects: 119/118; 639/766/1130/2798; 639/766/119/1001; 639/766/119/995; 639/766/119/997; Approximation; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; electronic and spintronic devices; electronic properties and materials; Humanities and Social Sciences; Hybridization; magnetic properties and materials; Manganese; Metals; multidisciplinary; Physics; Science; science & technology - other topics; spintronics; Splitting
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep07512

Half-metallicity in materials has been a subject of extensive research due to its potential for applications in spintronics. Ferromagnetic manganites have been seen as a good candidate and aside from a small minority-spin pocket observed in La 2−2 x Sr 1+2 x Mn 2 O 7 ( x = 0.38), transport measurements show that ferromagnetic manganites essentially behave like half metals. Here we develop robust tight-binding models to describe the electronic band structure of the majority as well as minority spin states of ferromagnetic, spin-canted antiferromagnetic and fully antiferromagnetic bilayer manganites. Both the bilayer coupling between the MnO 2 planes and the mixing of the | x 2 − y 2 > and |3 z 2 − r 2 > Mn 3d orbitals play an important role in the subtle behavior of the bilayer splitting. Effects of k z dispersion are included.