Structure characterization and magnetic properties of oxide superlattices La 0.6 Sr 0.4 MnO 3 / La 0.6 Sr 0.4 FeO 3

Oxide superlattices composed alternatively of ferromagnetic metal layers of ${\mathrm{La}}_{0.6}{\mathrm{Sr}}_{0.4}{\mathrm{MnO}}_{3}$ and antiferromagnetic insulator layers of ${\mathrm{La}}_{0.6}{\mathrm{Sr}}_{0.4}{\mathrm{FeO}}_{3}$ were fabricated on ${\mathrm{SrTiO}}_{3}$ substrates by pulsed laser deposition with controlling each layer thickness on an atomic scale. The near-perfect superlattice structure with atomically flat interfaces was verified by multiple peaks from Laue function in x-ray diffraction patterns with use of synchrotron radiation. An increase of antiferromagnetic ${\mathrm{La}}_{0.6}{\mathrm{Sr}}_{0.4}{\mathrm{FeO}}_{3}$ layer thickness from 2 to 5 unit cells induces strong magnetic frustration around the superlattice interfaces, leading to reduction in magnetic transition temperature and ferromagnetic volume, while increasing the resistivity and magnetoresistance at low temperatures.