Surface antiferromagnetism and incipient metal-insulator transition in strained manganite films

Abstract

Using first-principles calculations, we show that the (001) surface of the ferromagnet La${}_{1-x}$Sr${}_x$MnO${}_3$ under epitaxial compression favors antiferromagnetic ordering in the first few surface layers, coexisting with ferromagnetic bulk order. The change in magnetic order is accompanied by a marked surface-related spectral pseudogap, signaling a metal-insulator near-transition at the surface. All surfaces exhibit huge outward relaxations an rumpling of the MnO${}_2$ and LaO surface planes, causing a distinct shift in work function. The AF phase is an extreme surface-assisted case of the combination of in-plane AF super-exchange and vertical FM double-exchange couplings that rules magnetism in manganites under in-plane compression.

6 figures, 1 table, general revision

References in corpus (5)

• Phase Separation in Electronic Models for Manganites
• Ab-initio electronic and magnetic structure in La_0.66Sr_0.33MnO_3: strain and correlation effects
• Ferrodistortive instability at the (001) surface of half-metallic manganites
• Double exchange-driven spin pairing at the (001) surface of manganites
• Magnetic reconstruction at (001) CaMnO${}_3$ surface

Cited by in corpus (3)

• Strain-induced magnetization control in an oxide multiferroic heterostructure
• Persistent half-metallic ferromagnetism in a (111)-oriented manganite superlattice
• Emergent half-metal with mixed structural order in (111)-oriented (LaMnO${}_3$)${}_{2n}$|(SrMnO${}_3$)${}_n$ superlattices